A couple things:

1) Most are twatter blue checks and get paid for their content and it can be significant. If they've built bases outside of BTC, they rake in even more and most cross pollinate into econ, investing, etc. I know someone personally that is a small account and makes several hundred (to low thousands) bucks monthly for shitposting. 

2) Engagement is still better there. I know some of you guys get great engagement here, but mine is minimal even when I spend time responding to other's content. So they're unlikely interested in rebuilding that. 

So I guess what I'm getting at is that between getting their welfare and engagement, they're willing to sacrifice the other stuff. Toss in the fact that there are UI/UX challenges (and some devs cry when you bring them up), I don't really blame them for not joining us.