nostr:npub17f6anpj5vk0e4qzn3mcxwrahlj5qyqu363u6ayd07dtssx4vuh5qv0hyrn there are many more protocols out there than just XMPP and Signal, what about say Nostr, WebRTC  and others? So which one would it be then? That is very likely why we have so many - nobody ever made any decision for everyone, so all platforms went their own way. That really needs to change to at least have something to interconnect.