There are a couple of layers to this I think. At the base layer, if you are competing, literally to be the very best, then at a certain level you have very little incentive to share tech. To paraphrase Xian, “if your tech is ‘out there’, then you don’t have any tech”. When you’re playing the best players in the world, holding back on that last little bit of knowledge can be the difference between 1st place and the rest of Top 8.
I’m probably an upper mid-tier/lower high level player if I had to guess, and even I have hang ups about just broadcasting every little thing my character can do in all situations. We were just talking about this on the Hisako forum - I’m more than happy to answer any direct questions anyone might want to ask about my character, both here and within or after a game, but at the same time, I don’t necessarily want to post a general blast that says “here’s all my best setups, and here’s how to beat them!” I’ve on the whole been constructive and instructive in helping other Hisako’s get better I’d like to think, but at the same time I also want to be able to hit someone with something that’s a little unexpected the next time I go to a tournament. Being too free with your tech makes that a heck of a lot harder, and that’s just a fact. I think within a character community though, it’s generally a good idea to share (and I do) - helping one another level up your game is good!
The other layer to this question though is just the market for it. I love the ultra combo forums but let’s face it - the vast majority of posters here don’t give a crap about advanced tech or really leveling up their games. I remember Hero of Time posting a Jago tech thread in the character sub-forum, and he posted a bunch of videos and stuff about good Jago instinct combos. Then he posted another string. And then another. And no one cared. A person or two popped in to say “this is cool, post more”, and that was it. That Jago tech thread had almost no replies, and no one except for Hero posted anything. Why should he keep posting tech if no one cares about it?
Kim Wu has a tech thread, and it has a decent amount of replies to it. And it is vastly outweighed by stupid complaint topics about her shorts or her face or why isn’t dragon kick more like Orchid’s slide type of stuff. At a certain point you kind of just throw up your hand say “eff this, you people are ridiculous and I’m not wasting any more time interacting here.” A lot of the character sub-forums are like that, where people seem quite content to discuss aesthetics and other things, maybe complain about how something is OP and needs to be nerfed, but very few deep dives into what that character is actually capable of. That’s fine - that’s what those people like to talk about. But if that’s the only type of person who visits the sub-forum, then that nitty-gritty gameplay stuff gets left behind.
One thing I’ll give the Kan-Ra players - those guys are serious about trying to make their character work. They talk setups, strengths, weaknesses, etc. a LOT. But they are able to do that because when someone posts those things, their fellow players actually respond and reciprocate. You can’t put it on the pros or the streamers to carry this conversation, because it is on the players themselves to start and continue it. LCD or Paul B may be able to start a thread about a cool setup, but it’s on the rest of the community to keep that conversation going. And in the absence of those pros or streamers, it’s on the community to start them as well and show that there is an actual market for it. Not too many pros visit the Hisako sub-forum, but that hasn’t stopped us from talking a lot of shop about setups, MU’s, and all kinds of other things to help fellow Hisako’s level up their games.