The solution in my mind is simple (and therefore entirely possibly wrong): keep autonomous communities small. I like to think of this as the "Tower of Babel" p

The solution in my mind is simple (and therefore entirely possibly wrong): keep autonomous communities small. I like to think of this as the "Tower of Babel" problem, where basically all the world's people cooperated on one monumental task, and God "confused their language" so they couldn't complete it. We see this pattern any time people form a critical mass: fragments form, there's a falling out, and the whole thing comes apart. Take any sufficiently old group of people and the pattern asserts itself. The great thing about the internet is even if all the primary communities are small, it's trivial for members to inter-mix on their choice of small communities, self-selecting for culture fit rather than requiring armies of moderators to keep the conversation on track (though some moderation is still necessary).