OK so my RPG group uses Discord heavily, they're liable to be up for a switch... What's the situation for video chat?

I quite like the idea of the forum coming back, eg

Discourse - Civilized Discussion

What is Discourse?

Discourse is the 100% open source discussion platform built for the next decade of the Internet.

Not that this is useful for your group, but thought I'd mention it:)

i think flotilla is a good start, but needs additional features to be able to compete with Discord's offerings. i thought Universes was the answer to that, but that initiative has stalled sadly.