That’s why it’s less janky & doesn’t take minutes to join a room unlike Matrix. WhatsApp to the XTENSIBLE part of XMPP & extended it in a proprietary direction, but at least you have the option to easily do so with XML.

I don’t know what Matrix is giving users other than the eventual consistency model of chat, but most users don’t need the entire chat history of everything—you could argue it is an anti-feature that makes self-hosting too expensive in comparison & also leads to chat overuse/abuse ala Slack/Telegram/Discord where folks treat it as a forum that you can barely search when you have an account while being authenticated & where messages/topics get easily lost. For instance, you can replace an ’announcements room’ with a Atom feed.