God why are all crying about XMPP? If you want to make it more popular just start using it yourself. If you don’t have anyone to speak with over there just speak with me (seriously DM me).
Also we have a lot of open source alternatives by now so XMPP is just one of many good options which means that the people will go whith what they feel comfortable with. Trust me, if XMPP would be the only decentralized, open source chat protocol around I’d be using it exclusively and many others would probably too.