The place has essentially done three things all related:
got elderly and staid;
developed a monoculture;
reverted to the mean by prioritising societal taboos, squeamishness, prudishness etc over robust rationality, uncomfortable facts etc when the very thing that used to make the place interesting (to me) was the opposite - driven no doubt by the frank nature of Cecil’s column.
GQ and GD used to be the main forums here, and it’s still where I go first, but the big threads tend to happen in CS, Politics, the Pit and (to a lesser extent), IMHO.
User avatars! I must have argued for 10 years that they would make sense and not bring the forum down, and I do feel vindicated. It’s not that I want to see cutesy pictures, it just helps with mentally tracking who people are and who said what.
Not to fight the OP, but I think what’s great about SD is how little it’s changed. I joined SD in 2006 and there are no forums from that era that I still follow. They all either fizzled out, or fell to the extremists.
I think the kind of forum you are alluding to not only exist, but are massively more popular than the humble SD. Most will have something like “truth”, “freedom” or “patriot” in the name.
Y’all practically raised me. 
“You, alright?! I learned it by watching you!”
Some specific types of posts have been mentioned but the overall humor of this site has disappeared. I just checked the last 20 threads shown on the home page, none of them would be considered to have anything humorous. Coming here use to mean at least one good laugh, now days not so much.
A long time ago, the subject of what would happen if you panfried semen came up and so a doper did it and reported back. This was admired as dedication to factual enquiry.
Today, in FQ, a person refrained from posting the definition of a certain word because it involved sex. Needless to say, there are no (written) rules, stating that sex can’t be mentioned in FQ. Culturally however the poster was probably wise, because not long ago, I saw someone get modded for posting an extremely mild and non-sexist slightly sexual joke.
None of this has anything to do with highly counterfactual right wing views. But your assumption to the contrary is probably illustrative.
You’re kind of making the point that any deviation in the conversation from some well worn paths is not welcome. That the progressive conversation circa 2023 can only go certain predictable places, and deviation from that is a sign of decline.
I didn’t mention “right-wing”. But your assumption to the contrary is probably illustrative 
Sorry for the slight hijack.
It’s just that I visit a number of right-wing forums, out of interest and also to be the sole dissenting voice there. And the mention of “societal taboos” and “uncomfortable facts” immediately reminded me of those kinds of forums, where they claim that their ideas are being blocked elsewhere because of prudishness or whatever. Rather than their ideas being hateful and poorly-argued.
But fine, if that’s not what was being alluded to here, I apologize and let’s park it.
Makes me glad I erased the post I almost posted just now.
Why didn’t you start a “Killers of the Flower Moon” thread?
That’s actually a rhetorical question. I think a lot of the change on this board is posters aren’t as eager to start threads as we used to be. It’s like a middle school dance–everyone is waiting for someone else to start dancing first. You see this when moderators shut down hijacks and posters complain about it as if they’re not allowed to start their own threads.
The flip side of this is posters who are just here for arguments and contrariness. I don’t mean trolls, I mean posters who are knowledgeable, but assholes. They hide their jerkness behind being correct. They actively discourage others from starting threads and asking questions.
Bottom line, we need to be the posters we want to read.
These are good points. I’m not sure how to reconcile some things, like a desire to quash expressions of misogyny and sexism, especially in supposed humor, with a free-wheeling non-prudish atmosphere that is interesting to read and participate in.
Presumably someone with access to the servers might have some information about number of active posters over time?
I’ve only been around for a few years. At the moment it rather reminds me of the earlier days of Usenet (dating myself there), when access was usually only available to engineers at computer companies and academics or grad students at universities.
Discussion was usually fairly on point and polite. Before Usenet degenerated into a cesspool of flamewars…
I ask fewer questions here because people nitpick the questions to death rather than engaging with them in good faith. I sometimes read a new post and think, “I know how this will go off the rails,” and I’m often right. Then I just back away from the computer altogether.
Another thing that has changed for me is that there are fewer people here so each active contributor is a bigger part of the pool. When I first started lurking here more than ten years ago, there were loads of posters and I never recognized anyone’s names. I judged their views solely by what they wrote and everyone got a fresh chance to make a first impression with me because I never remembered what they’d written before. Now, with a smaller pool of posters, I generally have opinions of them, which colors my views of anything they write. The upside is that there are some posters that I know I want to read and occasionally, I look forward to their posts even when they haven’t arrived yet. For instance, I knew @Northern_Piper would eventually find his way to the post asking about the Statute of Westminster and when he did, I was glad for his contribution.
We all have our niche.
I gave up posting a LOT of factual medical experiences (all of which I naturally made HIPAA compliant) due to constant assertions from other posters that my recounting said experiences violated HIPAA.
We have lost a lot of the specialized knowledge that the board was known for. Before I could have asked what my son’s P1200 code on his 2007 Mazda CX-7 meant and I would have gotten correct answers along with how to do the repairs. Question on the Space Shuttle re-entry temps would have had someone ask their uncle who was the lead tester on the insulation tiles. Now it is threads that go off on tangents or politics. It seems some days that if I ask if anyone else if they liked the Priazzo from Pizza Hut that within 5 replies someone will rant against “the chee-toe insurrectionist”. Threads seem to go round-and-round because people are not reading for comprehension.
I agree with Princhester is that the board is becoming more of a monoculture and with bump that for certain political views, dissent is not allowed. I can’t quite put my finger on it but Factual Questions is different somehow. That use to be the first forum I would visit and sometimes I don’t check it at all. Some threads like the college football thread should be getting 20 posts a day and now we’re lucky if it gets 2. This is turning into more of a political site than anything else and that trend does not seems to be letting up.
But one thing that has stayed the same is (with one exception; there’s always one) a really good group of mods that should have their pay doubled.
When I was in college, at RPI, there was a student run service where you could call this number, and there would be someone there to answer any question you might have had. About anything. It was so long ago I can’t even remember what they called it, and it doesn’t exist anymore because Google.
I drop this in here because the types of questions people used to ask other people are trivially asked to the Internet, and you get a good answer right away. Like the P1200 code on an Mazda has to do with the fuel injector, and if I wanted to repair the fuel injector, some guy on YouTube probably has a video about it.
Where the SDMB excels is in getting a competent human being to talk with you about whatever your question is. Often when Google can’t really help.
The political monoculture is an issue, but when you have people who demand a well supported accounting of your ideas, the current slate of conservatives (at least USA conservatives) can’t manage it.
In the past, attacking or otherwise demeaning / diminishing women, gay people or trans people wasn’t considered “being a jerk”. We changed, and I’m happy with that change, it’s the right thing to do. I’d rather be welcoming and boring than exclusionary and exciting.
It’s hard to be new here. People probably get scared off quickly.
Some of us are just too committed to being dumb and needing our ignorance fought.
I don’t see it. There’s nothing at all about progressivism in that post. They instead seem to be pointing out the types of places that claim to prioritize “robust rationality and uncomfortable truths” over “societal taboos, squeamishness, prudishness” tend to actually just become cesspools. It does not solve the “echo chamber” problem at all, but actually makes it worse.
This board has always had “don’t be a Jerk” as its number 1 rule. And I believe this is for a reason. Rational conversation is difficult when people are able to use emotionally provocative, hateful language. A rational person who wants to have rational conversation will try to minimize provoking emotions because they get in the way.
In short, putting some sort of civility first is actually advantageous for being able to have “robust rational conversations.” Softer language makes it easier to discuss “uncomfortable truths” without it spiraling into people bickering.
The board used to be less kind. It has become less tolerance of jerkishness. But I see that not as a regression to the mean, but growth and maturity. The mean online is being rude and hateful when people disagree. It’s better that we can disagree without getting so heated.
And I don’t think the current board would have a problem with discussing the pan fried semen question. We recently had a question about what poop tastes like, and that didn’t get shut down for squeamishness.
Now, granted, we are far more strict on misogyny and racism and such. But I don’t see that as a problem. Those aren’t exactly rational, after all.