The whole post is basically showing pretty much features lacking that are otherwise quintessential for social media. Can't see posts, can't see replies, can't see trends, can't search etc. I mean at this point why even use it? It's like having a Ford Mustang in your garage that doesn't have tires and steering wheel but hey that V8 engine is sure nice.
If your preferred experience of social media is sitewide trending stories, or searching for topics, single-person Mastodon servers aren't a good fit for you. If, like Julia Evans, you have both a large audience and a network of people you talk to on the regular, it's probably pretty OK.
If Mastodon succeeds (I'm rooting for it), I expect single-person servers, delivered by hosting providers like Masto.host (but a generation or two away, like Blogger vs. the first generation of blog software) to be the normal way people use it.
At this point I think most people who been online long enough have a network that’s been sustained across many different platforms. Federation is great for these sorts of people when it’s used in the way that you’ve described.
Centralization still has its use as a meeting ground. The “public square” concept can still apply, but the thing is that it’s unhealthy to spend all of your time there and private/controlled gatherings are people can get a break and cultivate more unique bonds. Mastodon is interesting because it gives people the option to have both (public square or private hall).
I almost wish I'd never made a personal site and just done GitHub pages, even DokuWiki in the cloud isn't perfect.
"OK, but I made the square tyres myself and that is all that matters to me.
I also don't need rear view mirrors either because they are far too distracting."