The Kinda part is that your identity by default is backed by a DID that delegates authority to specific keypairs. The keypair that your PDS uses to sign is included in there automatically, but on account creation you can currently set a backup keypair that allows you to manually sign identity operations.
I have probably the least understanding of how this part of the protocol operates. Part of that has to do with the new (to me) concepts and the rest is open federation not being in place. I think something like this would be really useful and would prove your bonafides to others that Bluesky PBC is serious about being billionaire-proof.
Congrats on opening up registration!
My only feedback would be: I'd love to read a real deep dive on just bringing in your own did:web and using a custom PDS. The DIY AppView and/or Relay is super interesting, but that more straightforward concept of "you own your identity and you own your data" is such a powerful hook that I'd love to be able to share something straight from the docs.bsky.app domain on how to do it.
You can't do this today on the main network, no. Apparently they'll be "rolling out an experimental early version of federation" sometime later this month.
As for credibility on that timeline, the only major missed deadline they've had that I can recall was on making posts visible to those without an account. It was slated for (IIRC) late November/early December 2023 and launched December 21, 2023. I believe they overhauled the frontend as part of that work and it delayed things.
Also, they have already blessed one alternative DID method (`did:web`) and are open to slowly expanding that set (https://atproto.com/specs/did).