Yes on the uncentralised options! Except that they'd probably work well in terms of performance and caching etc, and probably wouldn't result in more centralisation than we've seen already from mastodon and mastodon.social.
If the software were open, then you could hope/expect multiple instnaces to be run with different focuses in terms of topics/niche-instances and policies around moderating/banning accounts. Also, different UI designs, which would be important!
@maegul @dimillian @ncrav @aral Maybe there's an opportunity to build a great #smallweb solution :)