I would submit that brown/black belts not wanting to really debate technique with each other or ask questions is one of the reasons online discourse tends to be so low level. Any time i ask a question here, everyone automatically assumes that I'm a white belt with no clue what I'm doing. Because how could a brown belt not know the answer to that question? Thing is, I generally do know an answer, but I'm looking for others. I don't think a lot of upper belts can handle that though, and either their ego prevents them from asking, or it tells them the answer they already have is always going to be the best, or that they already know all the answers.
On the debate side, telling a white belt they're wrong, even as another white belt, is borderline meaningless: they're a white belt, of course they're wrong. On the opposite end of the spectrum, tell a black belt they're wrong (and let's face it, occasionally they are, and sometimes they even make YT videos of it) and you've suddenly caused WWIII. Not only are you questioning something they've put countless hours into, there is a significant chance BJJ is their livelihood, or at least part of it. You're potentially criticizing the way somebody puts bread on the table, and people can get their feelings hurt pretty significantly, so everyone shies away from doing it.
I just wish it didn't have to be this way.
The main reason I am not that interested in that much technical discourse anymore is because eventually you get to a point where you realize that technique is not that important anymore. I think I am now at that point.
This sounds like heresy, but I think it is very true. Beyond a certain point, you just won't get any better looking for pure technical answers to things. As you noted, there are lots of different "right ways" to do things. Knowing ten different right ways to do something technically certainly won't make you ten times better. It becomes a futile chase after a while.
Even at lower belts, I've noticed that consistently the best competitors rarely spend much time debating technical points with each other. I mean there is usually an exchange of ideas, but they do not debate the "optimal" way nearly as much as many others. And, strangely enough, these guys usually crush the many others in competition. At this point, I do not think that is merely a coincidence.
I believe HOW you train is much more important than WHAT you train. And how you train is fairly well known and consistent across all successful guys. The biggest block is that many people simply do not wish to train this way because it is hard. That's fine, but you can't substitute encyclopedic technical knowledge for it.
I competed for the first time in over a year recently. It was a local tournament, so I had to take a match with an opponent about 50 lbs heavier to get any matches at all. He was a brown belt, and I was a black belt.
I ended up winning in pretty dominant fashion. Most people chalked this up to superior technique given the significant size difference. But I was in the match, and we were about even technically. Just like almost every other opponent I have faced since purple belt. Technically, it's close enough to not really matter. My first scoring move was the basic flower sweep from closed guard. I learned that from anaconda on this forum back when I was a blue belt, and I haven't changed it much since.
What I think really made the difference was my attitude, training philosophy, mental preparation, gameplan, etc. For example, I warmed up 30-45 minutes before the match. I rolled with training partners, drilled my initial entry for my gameplan, and jogged around. My opponent spent this time watching other matches with his arms folded. I had an edge here.
There were a lot of other non-technical edges too, but there isn't much point in going over each one of them. I think the point is that I won based primarily on stuff that isn't going to show up on a YouTube video or an MBO subscription or an online forum discussion.
So the main reason I'm personally less inclined to wade into technique debates is not because I think I know everything there is. Even more so than when I was a blue belt, I know very well now that I do not. I also know that there is no hope that I ever will.
Technique is the easy route that everyone takes. But it has diminishing returns for me at this point. I get much more mileage out of doing the "hard" things in training that others are lazy about. That makes the difference for me.