@elduvelle @BoydStephenSmithJr @davidculley
it's a pretty complicated question. there isn't really a technical definition for what federated vs. not is that maps onto what people mean when they want something to be federated for political or social reasons.
e.g. bluesky is already "on multiple servers" in the sense that it is possible to host your own data (and a small minority of people do), but bsky the company owns the rest of the parts that people think of as bsky - the relay (thing that aggregates all the posts on all the self-hosted data servers) and the appview (the thing that turns those aggregated posts into something usable, the app!). There are other apps and relays than bluesky's, but for reasons that are very boring to read and write, i believe there are insurmountable structural barriers to realizing anything that might look like a "truly" "decentralized" system (waving my hands over those terms for now) where one can actually be totally independent from bluesky the company.
the fediverse has some similar problems - the reliance on mastodon the software and mastodon.social the instance being similar, but e.g. if mastodon the company were to suddenly get bought and turn maximally evil it would be comparatively simple to fork the software and preserve much of the network (except mastodon.social, where accounts would be lost/trapped in a max-evil situation). if bluesky the company were to suddenly get bought and turn maximally evil (or slowly get juiced by its VC backers, which is more likely) there isn't a comparable path to be rid of it: bsky accounts are infinitely more portable than activitypub accounts, but if you have your data hosted by them (as the vast majority of people to) you have basically the same problem as mastodon.social - while the data structure is very portable, the server admins could just turn export off. bsky the company also owns the thing that translates your handle into the long unique value that represents your identity, and could just refuse to change where that points to and refuse to allow any other data hosts but their own (that's less likely, being able to host your own data isn't really that important to decentralization as a political goal in the atproto system, the rest of the infrastructure is what matters, but just an illustrative example). They also own the thing that makes it possible to see the posts (the relay) and also the thing that people use to see the posts (the app), and again while it is possible to make independent versions of these, the switching costs are enormous and introduce a combinatoric complexity that makes the apparently impossible feat of "choosing an instance" look like child's play.
So like the intention is to make a decentralized system, and parts of it are, but large parts of it are not and in my opinion are structurally impossible to make truly independent, which is why i haven't thrown in my lot with atproto - because if it wasn't, i like a lot of the other ideas, and the tech stack is definitely much more attractive.
edit: i should clarify, the bsky devs have so far shown themselves to not be maximally evil, quite the opposite, and i believe that they believe they are building with the best of intentions. The problem is that VC money makes you do bad things you might not want to do, and as long as you are an indispensible part of a system, you are a liability to that system being taken advantage of.
