I see the former just as a subset of the latter. ie Twitter is huge, but there are sub-communities that exist within it (some well managed, others not so much)

I see the former just as a subset of the latter. ie Twitter is huge, but there are sub-communities that exist within it (some well managed, others not so much), and Twitter is building community features to that point. Twitter can certainly do a better job of moderating its sub-communities, taking into account shared values and context, but I still don't see how the solution is to have users deal with content moderation.