Nowadays I can't come up with any good reason to use XMPP since there's Matrix and https://riot.im/
XMPP has adapted over time to support various chat and instant messaging features that we today take for granted. These adaptions come in the form of Extensions/XEP. I remember spending two hours with a geek friend to configure something that resembles what we get from any other instant messenger today (working across multiple devices).
Meanwhile, Matrix just works. Granted, UX involved with the key management associated with E2EE was not what it should have been. But, that has largely been fixed in v1.0.
Wouldn't spend the time to get into XMPP, if I didn't already have a decent network of friends there. And yeah, there's a XMPP/Matrix bridge available if you decide to go Matrix. https://matrix.org/docs/projects/as/matrix-xmpp-bridge.html