And Libervia (disclaimer: I'm the lead dev). It also implements SFU including components (based on Galène), but I'm reworking design on this part.

Also note that Libervia is using a backend/frontends architecture with a D-Bus API, you can use it to make your own frontend with any language you like.

I went looking for more info on Libervia and noticed your site is down.

Yes, I'm having a DDoS attack these days, no idea why somebody would do that to my small server. I've deployed counter measures so the site is more or less usable, but the attack is still going on.

Jingle is P2P with an optional server middleman for firewalled connections only no? I haven't seen any support for actually hosting a voice server with XMPP, only just allowing clients to figure it out themselves. I'll give it a look either way.

Indeed, Jingle is for establishing connections, P2P when possible, but there are lot of extensions around it.

I've proposed a specification for SFU hosting (check https://bloggeek.me/webrtcglossary/sfu/ if you don't know what's a SFU), and wrote a component based on the excellent Galène SFU, as well as client implementation (in Libervia) as part of a NLNet/NGI grant (https://nlnet.nl/project/Libervia-AV/).

XMPP council (disclaimer: I'm a council member for the current term) asked me to some modifications and to re-propose, which I'm about to do. I couldn't find the time so far (cause I'm working on ton on stuffs), but will go back to it very soon.

To sum-up: this is very much worked on.