I got distracted from my work so I made some Continuwuity propaganda. Continuwuity is a lightweights Matrix chat server that you can self-host pretty easily. Give it a try :3
Okay, I don't know the history. It is unfortunate to not have project differences spelled out, because the truth is most of us know nothing about these things. Sounds like a no, but would it be possible for the projects to collaborate?