Does it require people change defaults? If so then 99% will never use it.

A system or protocol is whatever the easiest user journey is. Anything outside of that will never be seen by many users unless there is some value to be gained by going there. And that value has to be something gained now, not a hypothetical like insurance against future closing of the network. People don’t like to buy insurance.

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.