@RadiantFlux that's a way to scale, sure. But more decentralised sites will lead to more admins needing to do work. I bet many of them are eager initially, and as life happens their prioritisation of mastodon admin work may fall. There's bound to be some consolidation at some point.
I'm not saying it should/will consolidate to a single site or even very few. I'm just not sure that throwing volunteer admins with homegrown instances at the problem will work well in the long run. I can't imagine all those volunteers still putting in the work 5-10 years down the road.