I've been hosting a ejabberd instance for a few people for almost a decade now. It just works, takes close to no resources and needs almost no maintenance - just some trivial config checkups when migrating to newer major releases.
Around the same time I tried hosting a Matrix server with Synapse, but quickly stopped. It consumed a lot of resources when doing almost nothing, and it stopped running after an upgrade with some non-obvious error message, so instead of reanimating it I just abandoned it and moved to matrix.org with my personal account.
Ejabberd is a bit overkill for a few people though. Prosody could be easily set up in 15 minutes or less. Also the config doesn't break when migrating to new releases.