I think these are reasons that Mastodon and Nostr aren't ever going to have a critical mass of users, remaining a niche thing for people who care about the hypotheticals (which is fine). Imho, BlueSky is the only distributed social media project that has a chance of meeting users where there are with usable search, realtime discoverability, and other consequences of centralizing event-busses.
People wine about BlueSky being too centralized, but the fact is that this type of infrastructure isn't self-hostable. You can do social-media over email a la Mastodon (which admittedly is pretty great), but most people will trade that for a walled garden.
The big problem is that all this AT infra is pretty much charity, which doesn't feel sustainable. I wish it could be funded more like public libraries than ad tech.