I have a weekly Zoom call with a small group of photographers, or weekly one-to-one calls. I don't think I really need a centrally managed server for these - the scaling requirements are small. I would love a low-cost alternative where the host ran the server and it was always invitation only. Of course there would have to be simple client apps for MacOS, Windows, Linux, iOs and Android.

If such a solution came along, I would use it and get rid of my monthly Zoom fee.

PS: end-to-end encryption would be good....