Are we decentralized yet?

Can someone explain how Fediverse instances or any decentralized platforms deals with most obvious issues of decentralization? Like if I join some node then one day it's offline and all my data lost. I mean surely instances usually don't disappear without notice but it still a totally possible thing. Or what about those times when entire instances get involved in dramas and end up defederating? I don't want to lose my connection with potential friends from such instance just because of something like that. I even remember some time ago when there were news about Threads being federated some people deliberately gathered "signs" across lots of instances to collectively defederate from Threads and it's just ridiculous to me that this even happened. What all this talk about fighting censorship while actively engaging in constant "self-censorship" making own echo-chamber as tight as possible?

In ATProto, this is solved by not having "instances". Your data is stored on a personal server (which can ofc go down). However, your identity isn't hard-tied to that server. If you have a backup (making those more easily available is being worked on by people in the ecosystem), you can restore it on another host and point your identity there instead. So there's one level of indirection which prevents the problem you're describing.

Additionally, since ATProto decouples hosting of data from hosting of applications, there is no such things as "instances" having beefs and defederating from each other. The data flows one way (from PDS to apps). Apps may choose to ban certain PDS's but generally PDS's themselves are treated as app-agnostic containers of data. So intra-network social beefs don't translate to technological cutoff or loss of mobility. Social groups and communities are decoupled from hosting.

> Like if I join some node then one day it's offline and all my data lost

They just disappear. You're not appending to a long-term immutable blockchain-like archive. You're posting things to the internet and the nature of posting things to the internet (or anywhere for that matter) is that nobody guarantees they will be around forever.

> Or what about those times when entire instances get involved in dramas and end up defederating

Identical to "what about those times when Twitter bans someone whose tweets I want to read?"

> What all this talk about fighting censorship while actively engaging

Censorship and moderation are the same word

> Like if I join some node then one day it's offline and all my data lost. I mean surely instances usually don't disappear without notice but it still a totally possible thing.

This happened to me with julialang.social which just stopped running after the guy hired to host it was poached by Google and he lost all interest in the Julia language community. Lost everything. Not going to look back at activitypub as ATProto is the future for me.