Federation, at least the way email, XMPP, the Fediverse, and the production version of Matrix do it, is a half-assed approach to data portability. The biggest

Federation, at least the way email, XMPP, the Fediverse, and the production version of Matrix do it, is a half-assed approach to data portability. The biggest problem with it is that, if a formerly-good server goes bad (or goes away entirely), everyone who used it is screwed, because their identity is tied up in the server. This means your most important criteria for choosing a server is stability. In practice, most of the user base picks old, established servers, hoping that the past predicts the future, and cementing a small oligopoly who can then use their power to direct the network’s future. Real portability, like Matrix is working on and Scuttlebutt already has, helps with this problem. If your user ID isn’t tied up in a domain name, then you can try out hosting your own server, and switch to and from it without much risk, so more people will try it.