Jitsi supports audio, video, or both, in addition to screen sharing.
One use case Jitsi doesn't support that Discord does is "push to talk"; that's something I haven't seen a good alternative for, other than Mumble, which seems much less usable for other purposes. But for other purposes, Jitsi works very well; I've had thousands of hours of calls on it at this point.
In an ideal world, I'd love to see a web standard for a web app to request access to a single (user-determined) key, to allow web apps to do push-to-talk while staying in their sandbox.
Well, even if Jitsi doesn't have Push-to-Talk, you can still easily get it by using a hotkey to mute/unmute the mic system-wide.
For exampple, if you're on PC, MicMute [1] can be used for free, or if you want more customization, I would humbly present my side project, AutoPTT [2].
