I have been using XMPP for some time. Since May this year infact, and I love using XMPP and I cannot stop using it. I have come to host my own stuff because I thought when I'd switch to XMPP from matrix I'd just host a homeserver. I'm glad I did and now I am here writing logs on my gemsite as well. This is fun. Though even in this long period of time, I haven't gotten any far away online users on my server yet, just my family and some others. But as I even have them contacting them and messaging them became easier for me. OMEMO works great, though there's some rough edges with it technically. Nonetheless my experience with it has been a great plus.
When it comes to clients for XMPP, like tbh there isn't an actually good client anywhere at all. I love C and there seems to be a C XMPP client named `profanity` which is the only decent client it seems. I've been using it for some few months and it has been my main client now. I honestly like it, though its kinda limiting and sometimes I have felt like using a "better" client but there's none. it is honestly kinda sad.
There is another problem in the XMPP space. Some pubmucs (Public Rooms) have this CoC from joinjabber.org, which when I read about it found myself muttering "wtf?!" out loud. This was a hilariously discord like bullshit brought onto the XMPP space. What in the world. Some people even have thought about banning JJ's servers completely, and I have decided to not even join any of the JJ's mucs at all, none of their MUCs are enjoyable to chat on and no one should even join any of their CoC'ed up MUC at all!
OMEMO works pretty well, though from what I understand the identity crisis is still unsolved. There's thing "blind trust" that can take place, and you can have trustmode on automatic and trusting everything, which is stupid; you shouldn't. OMEMO works on per device from what I understand. So if you have trusted their first 2 keys at the start, you should not trust any more keys from them unless they say so (from their other client).
Nonetheless, I wish more and more people to switch to XMPP and make their life even better even though there's still major issues with XMPP still and XSF people are chilling ;-;