Yes I've been looking for the same thing. I created https://zsync.xyz with the goal of serving as a place for high quality discussion of any topic, but turns out it's pretty difficult to create a community since there's that whole chicken and egg problem.

If anyone has any ideas on how to create a community like this, I'd love to hear it. I'm really not a fan of chat rooms other than for casual chats between friends because there's no search engine indexability.

I guess in the meantime, I'd say Twitter is probably the best I think. Everyone's on there, and people are incentivized to increase their following. I just wish they'd do away with that 500 character limit since that confines longer form writing to Twitter threads and makes actual dialogue totally impractical.