Fediverse

I don’t think a nomadic identity is the same as an instance-less identity.

It isn't. (Source: I've been using nomadic stuff since long before any of you has even heard of the Fediverse.)

Nomadic identity always requires one main instance of an "identity container" with a valid Fediverse ID. That Fediverse ID carries in it the domain name of the server on which the main instance of the "identity container" resides. You need something behind the @. The clones have the same Fediverse ID.

So if you have a Hubzilla channel on hub.foo.social, hub.bar.social and hub.baz.social, one instance of that channel has to be the main instance, and the others are the clones. If the instance of the channel on hub.foo.social is defined as the main instance, it's hub.foo.social that defines the idea (e.g. bob@hub.foo.social). From a Hubzilla POV, the clones on hub.bar.social and hub.baz.social are bob@hub.foo.social all the same.

Instance-less would require a fully decentralised, peer-to-peer approach like Briar where (ideally) each user name only exists exactly once. And with no domain name attached to it.

And peer-to-peer in social networking sounds like an awesome idea until you have to run a full-blown, fully-hardened Web server on your iPhone on a wonky 4G connection, simultaneously sending a message to and receiving hundreds of messages from hundreds of other devices out there because you've got, like, 647 connections on your friends list. And then you wonder why your phone is so hot, and the battery craps off within hours.