No that's just hip marketing. There is one instance (and technically a way to host personal data that nonetheless requires creating an account through the main service). The code is open though.

If anyone is interested in decentralized micro-blogging, there is Mastodon, and if you are interested in short form video there is Loops.

Loops is not yet decentralized, but it is based on ActivityPub and planned for open-sourcing and federation after Beta testing. The creator is an established developer in the community, so the claim seems credible.

From what I gather yes and no.

The fediverse is decentralized as it uses a protocol activity pub to allow lemmy, mastodon, pixelfed, etc to all talk. Moreover, most of the servers (to my knowledge) are community run. For example lemmy.world.

Bluesky made a new protocol similar to activity pub that could be used in a similar way, but its only used by Bluesky. They have allowed other users to host their own servers, but Bluesky still hosts the main servers (from what information I could find).

It seems bluesky wants to be similar to Fediverse applications, but I would have almost preferred how Threads did it; they actually use activity pub, so from mastodon you could follow threads users and vice versa. The Fediverse community wasn't fond of Threads so most servers defederated (or blocked) the Threads servers.

I feel Bluesky is doing something similar to threads. Its a corporation first that wants you to think its like the community first decentralized social networks. My take is, better than Meta/X, but I stick to Fediverse applications.