They're also looking to implement OpenID2 so it can be used to log into websites just like Facebook currently can.

Yeah, owning ones identity and also your followers/friends/etc connection to your account should automatically be updated if you choose to move instances. This is what I believe will allow federation to flourish.

When the shortlived Great Migration to Mastodon took place last year, it was terribly cumbersome if you wanted to move instances — you would lose all of your friends again, at which point you’re required to somehow alert every account which follows you and expect them to go through the steps to add your new account. This is just too messy and for people who have spent years building their perfect social net, this is a pretty severe roadblock when one is forced to choose between a new instance with better culture but losing years of work connecting with interesting people.

I think federated networks are perfectly fine and a good first stepping stone into better decentralization, P2P usually has some problems in usability and moderation/administration.

Mastodon instances allow people with similar interests to live together as a community with a strong bond than what you'd usually encounter in purely P2P networks.