Copy-pasting a comment from Aurich (Ars Staffer):
I set up the Ars Mastodon instance, and speaking as a relatively educated and technically savvy person I found it extremely confusing. And the more I learned later the more I don't feel remotely bad about being confused, it's honestly pretty messy.
I put Ars on the main instance, and I think it was the right call. We're not going to maintain our own, at least at this time, and trusting a random instance that's very difficult to vet is kinda sketchy.
We ran a guest editorial a while back that I think really clearly outlines the various issues:
But you know, it's really okay. It doesn't have to be big, or popular or mainstream. As long as it survives and people like it? That's good enough.
I think going into an era of balkanization of social isn't the worst thing.
One of my complaints with Mastodon and similars is that you can't search only for posts of a specific instance, or temporarily mute a single instance from your feed. There's also some sort of "invisible wall" for Pleroma users (niche of a niche), as their public posts simply don't show up in public Mastodon searches, though I don't know whether that's a problem with Mastodon or Pleroma.