The issue with insular communities is they're insular though, and often by definition exclusionary. The nice part about something like reddit was if I picked up

The issue with insular communities is they're insular though, and often by definition exclusionary. The nice part about something like reddit was if I picked up a new hobby, I could reliably find a community for it there. If I take up kayaking, it's unlikely that the insular music BBS I'm on has more than a handful of kayaking enthusiasts on it, and for just a general hobby, I'm not even sure where I'd start on trying to find an insular community for that hobby. There's many interests I've ended up getting more involved in because I could easily join a subreddit that was about that without much effort, and then over the years, by osmosis, I learned and saw more of it while I was engaging with the other subreddits I was more active on. Smaller communities just don't offer that sort of convenient diversity of interests and experiences.