> unless you want to run a separate messenger infrastructure. Or if you S2S federate with the upstream server. Which is a core differentiator of XMPP and Matri

> unless you want to run a separate messenger infrastructure. Or if you S2S federate with the upstream server. Which is a core differentiator of XMPP and Matrix. Signal server(s) notably supported proper federation during their initial growth-phase but famously closed it off ("The ecosystem is moving"). Similar story as Google [Chat/Talk/Hangouts], which did federate over XMPP before they closed that down years ago.