To the extent that posters inclined to trolling and disrupting productive conversations are excluded, yes. That’s not what we usually mean by “exclusionary”.
First things first: First, let’s make this complicated.
I have no problem with excluding certain posters from things. I mean, that’s literally what topic or thread bans do.
I do have a problem with the idea of the Pit excluding everyone but a select group when that forum serves to bash people. That’s extremely toxic.
But no, I don’t object to keeping out certain posters or kinds of posters when there’s a good reason for it. That’s not even a new thing, we’ve been doing that for years, it’s just a new way of doing it.
I did, right at the start of this thread;
I wasn’t responding about opt-in, just the general idea of excluding people from the Pit.
Thread banning of course is nothing unusual, but that’s very different from the opt-in that is being discussed.
But on the idea of having to opt into certain threads, again I think that’s a potentially interesting idea.
It keeps casual lurkers who may be curious about actually participating in discussion from stumbling unwittingly into the pit and thinking it’s representative of the sort of behavior that is tolerated on this board.
Personally, I don’t think such a “protective” feature is necessary, but others, apparently, think it could be value added, and I’m just noting it’s an idea I’ve seen welcomed and implemented on another board.
The only people at risk of that are new people, and I wholeheartedly agree with the idea of restricting new people from posting there.
Also, if your concern is with people getting the wrong idea about the board because of what happens in the Pit, you’d best restrict them from reading posts also, and that’s a whole other thing.
We would have to fine tune the automatic changes of the users trust level from 0 to 1 and restrict trust level 0 posters from the Pit.
All of that would need to be done by an Admin. Our only Admin is Ed Zotti. This makes it hard to do any testing or quick fixes if something unexpected results from the tweaks to the settings. I don’t think any of this is going to happen and I’m not seeing a driving need for it either. I see some merit, but not a need.
So this falls under the category of “Want it, but not technically possible in the foreseeable future…and asking more vehemently/stridently isn’t going to change that”?
This sums up my feelings exactly.
It’s not a bad idea but it’s not necessary.
If it would really difficult to implement and might cause problems that are just as difficult to fix or undo, it doesn’t sound worth it.
Maybe if someday there is an admin with enough bandwidth for these sorts of things, this and other ideas could be tried out. 
When one of us wins the lottery / becomes president-for-life / ruler of the world and assumes control of this board, then, THEN will come all the changes, like it or not!
In all honesty, if I suddenly came into a lot of wealth, I’d give some serious consideration toward helping this place. No lie, I really like this place.
In the meantime, I’d subscribe again if we were able to.
And you (and I) better promise not to run it the way Musk runs X/Twitter.
May the fleas of a thousand camels infest my groin if I lie.
This is a whole other issue, and a much larger one. The sad passing of TubaDiva seems to be leading to the slower but inevitable death of a great discussion board that no longer has leadership. I understand that Ed has a great many other responsibilities, but the board needs a full-time admin. @engineer_comp_geek offered to do it, but was rejected because he’s not actually an employee, which is total bullshit. With the passing of TubaDiva and her dedicated enthusiastic leadership, the board is self-destructing. I’ve always been such a strong advocate of this as a place to have great discussions with intelligent people. Its impending demise is very sad.
ETA: In case some have forgotten, the fact that this place even runs at all any more is due to TubaDiva migrating the site to Discourse. One of the last things she did before she died.
Agreed, but Corporate policies are Corporate policies and I think we’re still operating under the principle of keep our heads low so they don’t notice we’re here and ask questions.
But that is speculation, the mods don’t actually know any more than the other posters.
I’m sure it’s AN issue, but IMHO it, like the visibility of the Pit thread, is far below our lack of outreach in seeking new people, as well as the general decline of long form text based message boards.
I mean even if we had full time admin, and subs were reactivated, those issues will persist.
Now if we were growing our population, then the issues with Trolling in the Pit and Muting the Pit would be fine next steps to address, rather than largely internal wrangling about interpretation on the fine nuance of rules.
However, we love to wrangle about the fine nuance of everything, so, win for us? 
This is an interesting discussion to have, but is rather off-topic for this particular thread, which was about why a specific troll was allowed to continue trolling.
@Miller has said they’re not trolling, or not troll enough for the Pit. Lots of others have disagreed, but it’s Miller’s party, so I think this thread can be closed and you can have this discussion about limiting Pit access elsewhere (I’d vote “no”, BTW).
No, it was about why someone you disagree with and want to call a troll can continue to post.
There is no consensus here, and the relevant mod disagrees that it is trolling.
If all I wanted was to call a particular someone a troll, I’d have used their name in my OP. Or in any of my posts in this thread.
Or I could just call them a troll in that thread, since it’s in the Pit. As opposed to avoiding the trhead while they’re trolling it up there.
Or I’d just post about them in the dedicated Troll Pit thread, which, mind you, I have actually done about other things.
This thread isn’t about the identity of the particular troll, it’s about why the trolling is allowed to stand.
Did I say there was?
There clearly isn’t. Just a seeming majority of those who’ve stated a definite opinion.
Yes, something I already acknowledged in the post you quoted from, Captain Obvious. Obviously I disagree.
Moderator Note
This is ATMB, not the Pit. You can make your point without resorting to insults.