Came across this on the r/selfhosted community. Still very much in the alpha stages, but it’s already got a Docker image you can try out for yourself, or try out the demo server.
Tried it earlier today, couldn’t get the voice/video chat to work right away on my self-hosted setup but the real-time chat was very snappy. Looks promising.
I have, and am, selfhosting Matrix, and it isn’t that big of a deal if you’re someone that, you know , self hosts things. That is just outside of what most people can or are willing to do. That’s totally fine, but finding a FOSS platform that will host a VoIP/video server for you and not try to monetize you is almost certainly going to be rare or short lived.