For the past year I had fun messing around with Docker containers, Moonlight/Sunshine and HW acceleration; so much so that I've ended up building a Gamestream server from scratch!
The basic underlying idea is to allow the followings:
Share a single server (possibly headless but doesn't have to be) with multiple users
by creating virtual HW accelerated desktops
whilst keeping remote mouse, keyboard and controllers completely separated
with low latency
It's still rough around the edges, and it needs more testing from the community; if you want to check it out, here you can read the docs and here's the Github repo.
They should all be supported but there's only so many types of HW that we can test. So far we've got reports of Nvidia, AMD and Intel all working in different setups.
That's great to hear. This might be the holy grail of game streaming server setups. I could build one strong server with one gpu and have it serve an arbitrary number of clients. Since they are all effectively Linux desktops, they should have a wide range of compatibility via WINE and emulators.
I did some more research and came up with another question: Does Vulkan work on AMD GPUs?
I'll definitely set up an instance when I get some spare time.
Once you have it mature, you should reach out to Craft Computing on YouTube. He did a ~16 video series on different ways to build a private game streaming server and I believe what you have here would be much more achievable for a normal person.