No it's literally just Nostr except you can only post to one relay at a time.
nostr:npub108pv4cg5ag52nq082kd5leu9ffrn2gdg6g4xdwatn73y36uzplmq9uyev6 is bluesky literally just activitypub wtf is it?
Discussion
The protocol (AT Protocol) is basically activitypub except more seamless switching between instances and following people on different instances isn't a clusterfuck like on Mastodon.
Bluesky is just a client for the AT Protocol, like Damus/Amethyst/Snort etc
Having said that, using a federated model like ActivityPub means it'll still have a lot of the inevitable centralization problems that AP has. Nostr and its relay model are much better at avoiding this.