Well, it depends on what you’re referring to.
There’s the promise that Bluesky will federate eventually, and there hasn’t been much indication of anything beyond whitelist-only federation that I’ve come across yet. Also they were boasting about having an ‘open protocol’ but yet there were significant disparities between their specification and what they had in production (even in a variety of light variations or typos of attribute names, etc).
Are you sure you’re not mistaking the DNS aliases as federation? Because that’s like no different than someone thinking they “run a server” because they created a Discord guild (per the Discord’s misleading marketing).
There’s also plenty of excuses and possibly ‘misinfo’ in their side as well regarding ActivityPub, of just making an excuse for making a whole separate protocol, where they initially hold federation exclusively to themselves for a period, so that they’ll always have a stronghold grasp on ‘their’ ATProto network (by user count and site age), and where development and direction on that network will be entirely dependent on whether the flagship instance bothers to ever support any third-party extensions to the protocol. It’s just as “decentralized” as the LBRY network of Odysee.
Also, when you devise a protocol, you don’t just have one group make it, then it’s on everyone else to adopt it; you have two or more separate groups make their own implementations of it, to test if the standard is even sane, rather than just figure out and test interoperability later. It’s generally a prerequisite to most standards bodies for a reason.
In regards of their remarks on ActivityPub: it’s operationally a meritocratic living standard; it’s not about what’s solely enshrined by the W3C nor how only one software (Mastodon) implements it, as their FAQ seems to imply their outlook on it. Also, majority of implementations just end up implementing it as plain JSON rather than full true JSON-LD support. There’s also no standard nor FEP that mandates double-at representation, that’s primarily a Mastodonism (more on the aspect of mandatory WebFinger resolution).
Also the remark that identity and data portability as not being retrofittable to ActivityPub, yet there’s discussions and efforts with proposed FEPs to establish exactly that. I reasonably believe we’ll have ID/data portability in some ActivityPub implementations before the day that Bluesky is full open federation, built on much more matured codebases. Much of the complaints of ActivityPub are being resolved as a larger meritocratic group effort (by proving it with code and implementation), but users evidently want to throw out entirely everything, just to gravitate to the newest shiny Venture Capital funded start-up, learning absolutely nothing from ditching out from Twitter.