Is it okay with you if they “discriminate” against those who post child porn or advocacy for violence?

Amazon is just one third of cloud services market (which 40 odd percent is various players, not even that concentrated). Big but in no way omni dominant.
Yeah, I’m sorry. Ma Bell was the only game in town under the notion that it was a “natural monopoly” protected by government regulation as a public utility. You just simply could not have a telephone line to your home if you would not use your monopoly carrier.
OTOH you do not have to use Google/Apple/Amazon/Twitter/Facebook to have a site or an online community. It just is a lot more resources-intensive and expensive for you to build that system entirely on your own up to where it plugs to the internet backbone, as opposed to using ready-made solutions that any underperforming middle schooler can set up on a pocket device, and therefore have all the mass audience there, but that are owned by someone else.
As others have mentioned, there is the matter of what is or whether there even IS something in our current world that fills the role of the “public square” where you do have an undisputed right to stand on your (own) soapbox under a tree and simply rant away and pass your home-printed handouts and as long as not directly calling for the King’s head everyone was free to listen or ignore. I don’t think we have a good answer to that question. Maybe the internet itself is the public commons, but how you get on it and make yourself seen is the soapbox you have to provide yourself, and most people don’t know how to make a soapbox.
I know what the first amendment is, but what the fuck is “freedom of expression”. Sounds like hippy bullshit to me.

Is it okay with you if they “discriminate” against those who post child porn or advocacy for violence?
I’m good with them censoring anything illegal

And yes, more than a freedom of expression thing it’s a markets thing. Heck, back in Ye Olde Days, seditionists and wingnuts had to just pass along mimeographed newsletters or self-publish their “books” and sell them in lower-end newsstands next to the porn. They were not entitled to be distributed by the major houses or sold at the major bookstores. Their letters to the Editor would just get tossed if they were incomprehensible or vile. That did not mean they were being deprived of their freedom, did it? The publishers and bookstores were not “common carriers” obligated to convey anything anyone wanted to sell through them.
This is very close to my opinion. By and large I don’t think social media companies act as common carriers. If the Post Office, UPS, or FedEx refused to service eg: Trump supporters I would see a problem. If internet service providers refused to offer service to people based on the content of their communications, I would see a problem. Amazon’s decision to ban Parler from its cloud hosting, specifically, does not bother me at all. Twitter’s decision to ban the President’s account doesn’t bother me because legally and technically speaking I see Twitter and other social media as a publisher, not a platform - section 230 notwithstanding.
~Max
So you’re fine with censoring advocacy for drug legalization?
IMO they should allow advocacy for legalizing drugs, but ban advocacy for legalizing child molestation.
Do you see the difference? Or do you think they should be treated identically?
If I were Twitter or whoever, I would say, “as with all other freedoms, your freedom of expression ends where mine begins.”
~Max

If courts can force custom content creation
Until you demonstrate the existence of court-ordered custom content creation, I’ll deny this premise and throw out the rest of your argument with it.
~Max
I don’t want to harsh anyone’s buzz, and I think there are some fine sentiments about fighting the overwhelming monopoly, but it looks like somehow, in an environment where there are no avenues, Parler has found a light at the end of the tunnel…
According to several sites, including Business Insider, Epik has agreed to host Parler. Parler registered its domain with Epik, a company known for hosting other far-right websites including Gab, according to publicly available WHOIS information. The news was first reported by James Iles, a writer whose blog focuses on domain names.
What was that, 4 days without Parler? Oh, the horror…the humanity…the trampling of expression…

Tell me how many media markets besides New York and Chicago ever had more than a single newspaper?
I’ve lived in Boston. During the ‘80s they had at least 3 major newspapers. AFIK they still have 2, the Globe and The Herald.
My tiny little Midwestern city had two vibrant, independent newspapers until about 15 years ago, one morning, one afternoon (The Journal and The Star). Those 2 merged into one. A subsequent purchase of the merged papers took it out of local ownership and the paper became irrelevant.
In the end we are getting fooled by damn Internet Hype because in the end there’s nothing in reality different here structure wise than pre internet except speed and ease.
If I wanted a radio show or a newspaper column, super, sell myself or my ideas to a publisher or broadcaster who otherwise was in no goddamn way obligated to give me a regular access and spot (except maybe some public access non private channels… maybe).
Twitter and Facebook are no different. I have no right to them. Sure I find it convenient but I didn’t build it, I don’t own it.
Back in the day these people, like my crazy fucking kkk adjacent relative, would buy and distribute neofascist tags like The Spotlight (even as a kid raised super conservative Spotlight was clearly fucked up, that none of respectable Republicans would touchbut nowadays it would be damn Trump central).
Just because internet made this all easier didn’t create a public right to absolutely force a private publisher - call it distributors if one wants not to get hung up on the publisher nonsense- to disseminate my speech.
So called conservative talking heads saying so are opportunistic hypocrites. I am sticking with foundational principals.

Maybe the internet itself is the public commons
For what you’re saying, bingo. The internet is the new form of public commons, analogous to streets.
Social media is rarely a public square, because they require you to register before speaking. You have to sign a private contract between you and the social media company. It’s more like a public event at a private venue.
Let’s say, for example, you operate a Twitter account. I regularly visit Twitter via the internet to read what’s new on your feed. Sometimes we have a conversation.
I say this is like if you hang out at the local sports bar, which lets you use their bulletin board and reserves a room in the back for you. I regularly visit the place via public roads to talk or see what’s new on the board.
If one day you’re doing something the bar owner really doesn’t like, eg: hitting on his daughter or something, tough luck, he’s totally within his rights to ban you. Maybe that bar is the only good hangout spot in town, maybe the only other restaurant is the Chum Bucket, it doesn’t matter.
~Max

Free speech is vastly more important than cake, and there are a lot less options for social media than bakeries. If it’s okay to demand the baker not discriminate, then it should be okay to demand the same of Twitter.
You’re mixing up restrictions on products with restrictions on customers.
Bakers are absolutely free to dictate what sorts of products they will or will not offer to the public. If a baker wants to maintain a policy of not selling penis cakes or other bawdy novelty baked goods, for example, then the baker doesn’t have to bake a penis cake for you, no matter how non-gay you may happen to be.
But if a baker does offer penis cakes for sale to the public, then they are obligated to sell one to a customer who requests one. Doesn’t matter if the customer is buying for a straight bride’s bachelorette party or a gay couple’s DragStags bachelor party. Even if the baker thinks that straight bachelorette parties are fine but drag queen bachelor parties are disgusting, the baker is not entitled to discriminate between the customers in selling them the same product.
What you and a lot of people seem to fail to understand is that what social media companies are selling is not access to their services, but rather the content that their members create for free. That’s their product, since that’s what brings in the eyeballs and the ad revenue. So social media companies are allowed to choose what kinds of product, i.e., content, they will carry on their site.
If a social media company says “We’ll allow political-opinion posts, but not calls for violence or hate speech”, or “We’ll allow pro-BLM messages of support but not pro-Trump ones”, etc., they are not discriminating against particular users: they are simply exercising their right to choose what their product line will consist of.
Remember the old saw “If you’re getting something for free, you’re not the customer, you’re the product”? That’s exactly the case in social media. If they block you for violating their ToS, they are not discriminating against you as a customer: they are simply discontinuing you as a product.

{…} If a social media company says “We’ll allow political-opinion posts, but not calls for violence or hate speech”, or “We’ll allow pro-BLM messages of support but not pro-Trump ones”, etc., they are not discriminating against particular users: they are simply exercising their right to choose what their product line will consist of.
And if you don’t believe that then go sign up at Parler or Free Republic and see how long you can post as a liberal Democrat.
(I lasted one post at FR for simply challenging someone’s claim about a law . . . conservatives can not be wrong by definition.)

Are social media’s recent bannings a freedom of expression issue?
“No”.

And if you don’t believe that then go sign up at Parler or Free Republic and see how long you can post as a liberal Democrat.
Ayup. People readily believe that when they sign up for a free account on social media, it means that they’re the customer of a service provided to accommodate their communication needs. (And to be fair, social media companies bend over backwards to fool users into thinking that’s true. “Connect with friends and the world around you on Facebook”! “See what’s happening in the world right now” on Twitter! How may I show you the world and cater to your lightest wish, oh Master?)
So how dare the social media company say it’s okay for that other user to post what they want to say but it’s not okay for you to post what you want to say? Simple: because what both of you signed up for was an unpaid job providing the company with the sort of content that it finds profitable and desirable. Complaining that the company discriminates against your content is like a purple alligator-skin handbag complaining when the store discontinues it because they’ve chosen to sell pink lizard-skin handbags instead.

So you’re fine with censoring advocacy for drug legalization?
IMO they should allow advocacy for legalizing drugs, but ban advocacy for legalizing child molestation.
Do you see the difference? Or do you think they should be treated identically?
What exactly is the difference? What precisely is the distinction you’re trying to make? In both cases we’re talking about advocating changing laws, as opposed to breaking laws.
You can certainly argue that Acme Web Hosting Services has a right to refuse to serve anybody, and can therefore refuse to do business with both NORML and NAMBLA (out of some kind of stance of “We don’t like controversy, dagnabbit! We just want to host people’s cat videos!”). Or, they could host NORML (since NORML quite frankly seems to be winning, and is increasingly socially accepted), but still refuse to host NAMBLA (on the grounds of, Ew!). But of course Zenith Web Hosting Services across town could refuse to host NORML (on the grounds that “Drugs are bad, m’kay?”) but could host NAMBLA (on the grounds of, fuck, I don’t know). Or, Crazy Eddie’s Web Hosting Services could do business with both NORML and NAMBLA (on the grounds of Freedom! And making money). All of which assumes that there are multiple web hosting companies out there, with different policies. (Which in the real world there still are.)
Any business could–and I suppose should–refuse to facilitate actual crimes: The buying and selling and furnishing of marijuana products in those places where marijuana is still illegal (which is still most of the U.S.), and the distribution of child pornography in those places where that’s illegal (which is still pretty much everywhere). But theoretically both NORML and NAMBLA are merely advocating that existing laws be changed.
AFAIK, the FBI would have no cause to forcibly shut down either of those groups (assuming, for the sake of argument, that neither group has crossed the line from “advocacy of changing the laws” to “facilitating the breaking of the laws”). And, if The Phone Company or The Cable Company decided that from now on, their customers would no longer be permitted to access the websites of NORML and NAMBLA, or just the website of NAMBLA (or just the website of NORML) using the networks of The Phone Company/The Cable Company, I think that would be an unacceptable thing for them to do. I think the inherently monopolistic (or, in many areas of the U.S., duopolistic) power of ISPs needs to be kept in check.
Whether or not Big Tech (Google, Apple, Facebook, Amazon) are in the position of pre-break-up Ma Bell…I dunno. Certainly I’m concerned by the concentration of power in a small group of very large companies. If we’re just saying “Big Tech should allow advocacy for [things I agree with], but ban advocacy for [things I disagree with]. Do you see the difference?” then, no, I don’t really see a principled distinction there.
At first listen I like that argument, but the counter argument is that there were still always many local news outlets on television as well. In fact per the link I gave up keeping those available was considered as critical in decisions regarding the 1992 Cable act and “must carry”:
At issue in Turner Broadcasting was the constitutionality of a provision of the 1992 Cable Act that contained a “must-carry” requirement.
Under this provision, cable operators with more than 300 subscribers and 12 channels had to set aside up to one-third of their channels for local commercial broadcast stations. In affirming the must-carry provisions, the Supreme Court ruled that these provisions furthered important government interests in promoting a diversity of opinions and ideas.
Point being that the precedence is that maintaining the diversity of opinions and ideas is a public interest and that large companies can be regulated to assure that such is accomplished.
I shed no tears over Trump not having Twitter to spittle forth from. But I do worry about a precedence that a future CEO may see the winds blowing to the Right and capriciously declare someone of a different ilk banned arbitrarily. I am sympathetic to Navalny’s arguments - that private companies can easily become an autocrat’s best friends and enablers, doing their censorship work for them, that minimally there needs to be some greater oversight than a CEO’s decision. He merely proposes committees with clear guidelines, transparency, and an appeals process. Others propose some other independent body. We’ve seen governmental bodies abused too easily this go around to think it should be there. And I am not convinced that doing nothing is safe as a long term approach.

Simple: because what both of you signed up for was an unpaid job providing the company with the sort of content that it finds profitable and desirable
So long as you’re in an At-Will state, they can fire you for anything.