I still love getting messages via xmpp from friends and family using my own snikket/ejabberd instances after years of use. Calls as well.
Video conferences via jitsi meet fill my heart with joy since the covid epidemic. These are also xmpp based. It's just a cool lightweight protocol.
Well yunohost seems to support prosody, that should work very well. Snikket is basically just prosody with some extensions preinstalled. If you want an xmpp server on yunohost you could just install prosody or alternatively run snikket in a docker container. Prosody might even be easier to setup if you can install it via the yunohost gui.