Fun fact: under the hood atproto bears many similarities to blockchain... it was funded in during the 2019/2020 crypto craze. I'm not too involved, but outside of a consensus mechanism, atproto looks a bit like a chain, kinda like IPFS.

I'm very deep into ATProto development, in particular I have the first Permissioned PDS implementation [1]. It definitely has roots in blockchain / federated, but makes tradeoffs for UX.

The more interesting perspective is a Plug-n-Play Distributed System [2]

[1] https://github.com/bluesky-social/atproto/compare/main...ver...

[2] https://atproto.com/articles/atproto-for-distsys-engineers