Running Steam and games securely
Is there a consensus on how to run Steam and games isolated from the main system? I've seen Flatpak mentioned in some Reddit post but I'm not sure how good the separation is. Everything about Flatpak sounds like an early work in progress, but I can be convinced otherwise.
I don't trust Steam or the closed source games at all. Currently I've got a second disk with a separate system for gaming, but I very rarely have the motivation to reboot. I want to game more (and spend less time on social media) but compromising my main OS is out of the question. Stuff in the home directory should be isolated from the games. Ideally no network access too, but Steam will not work in that case.
If someone has seen a ready made guide I'd be happy to read it. Any tips would be nice too.
KVM switch is the easiest way, you just plug both GPUs into your monitor, and switch between the two depending on if you want to see your main system or your VM. The Archlinux wiki also talks about "Looking Glass" which passes through the VM's display to the main system. I haven't tried this so YMMV. Alternatively you can run Sunshine inside the VM and stream to the main system. Maybe overkill if you are only using a single PC, but if you've got other devices you can stream to those too.
As a veteran to VFIO and GPU passthrough, I would recommend the KVM option first. It's often worth buying cheap workarounds to start with, before diving into complicated software and networking setups like Looking Glass or Sunshine.
Sunshine sounds pretty decent but yeah, one step at a time. Thank you.
Sunshine in general sounds very tempting, I don't play AAA games so an old laptop may be sufficient for most games, and the desktop clients are free.
Sunshine is actually pretty easy to set up. Just install it on the PC, and connect from a Moonlight client on the same LAN. The complicated part is if you want to get fancy with the networking, for example if you want to access it securely from outside the home, or if you run Sunshine inside of a VM and want to access it from outside the host. But if your laptop can handle the games you want to play, turning it into a game streaming server should only take an hour tops. Definitely easier than messing with passthrough and virtualization.