You are probably using something that builds on it. It's the IETF standard for IM, scales very well and it still seems to be the industry standard for large mes

You are probably using something that builds on it. It's the IETF standard for IM, scales very well and it still seems to be the industry standard for large messaging systems (WhatsApp, Zoom, Jitsi, Nintendo Switch presence... are known to be using XMPP). Cool community projects which also care about the federation aspects are jmp.chat, snikket.org or movim.eu (a federated social network built on XMPP PubSub nodes that broadcast ATOM items). There are communities that are on XMPP, but I currently use it mostly for friends and family.