Less buggy? I have had OTR and OMEMO fuck uo countless of times. XMPP only somewhat works when both parties use the same client. Multi user chats are abysmal, too.

That said, XMPP is great for building other communication systems since it’s pluggable and modular. If I wanted to build a chat system in an MMO or real time IoT communications for example, I’d certainly consider XMPP for its light weight compared to Matrix.