Bluesky offers no benifit to the user over activity pub. The server owner still controls the private key. It's useless.
Discussion
Yeah, if you wanted to make something as centralized as AP, just use AP even though it's a 10 year old protocol, it has a network effect. If you want to make something modern, interoperate with nostr. There is still a chance to do that, but should have been done earlier.