Self-contained online multiplayer with a single Qubes PC?

I saw the thread on Quake 3 and had a flash: Self-contained Qubes multiplayer where the PC contains both the server(s) and multiple clients.

I can see some practical uses beyond the ‘just because I can’ factor–a convenient setup for online-only games that already have private server support; emulation; speedrunning; single device multiplayer gaming (split screen or multiple screens)

Anyways, just thought I’d throw this out there to see what happens. I see a non-zero chance for this to be a way to boost Qubes’ visibilty.