@xgranade@wandering.shop
For one thing, Bluesky is an American PBLLC, not a German NPO. There's a lot more room for extraction in PBLLC structures.
For another, Mastodon does not own or control the spec to ActivityPub the way Bsky does to ATProto.
It's true that Mastodon has an outsized influence on AP, in that implementers have to worry not just about the spec, but bugs in Mastodon's implementation, but it's still an important distinction.
@xgranade@wandering.shop
But perhaps the biggest difference comes from the power dynamics. When Bsky backs people like Singal and Vance, that affects not just a plurality of ATProto users, but the near-entirety. When a user locks their skeets (again, ew), it's specifically a Bluesky-the-PBLLC account I need to interact with them.
Bluesky-the-company has far, far more control over ATProto users than Mastodon-the-nonprofit has over ActivityPub users.