The community separation also means it’s easier for a whole group of people to share the same space because you can post about 10 different topics and each other person will only see the specific ones they want by subscribing to just the communities they like, instead of seeing everything from each person they follow. I recognize like a few dozen frequent commenters here myself, and I don’t have to see them post about topics in not interested in because I just don’t go to those other communities, so I just see the overlap we all care about.