It seems like you haven't looked into it much since it's was feasible for last 7-8 years..

Linux hosts had GPU passthrough working well before commercial software had such options. Nowadays it's just work out-of-box with Virt-Manager that just run QEMU under KVM.

It's been working for years for 99.9% of games excluding some invasive anti-cheats that ban you for VMs, but there literally only a few games that have issue with virtualization.

I use Proxmox and GPU passthrough works just fine (via QEMU). Note that Nvidia GPUs have less issues with passthrough, at least last I checked. See this guide: https://pve.proxmox.com/wiki/PCI_Passthrough

But if you’re running a standard distro, there are guides for most them.

* Arch guide (excellent resource, applicable to all distros): https://wiki.archlinux.org/title/PCI_passthrough_via_OVMF

* Ubuntu: https://ubuntu.com/server/docs/gpu-virtualization-with-qemu-...

* Gentoo: https://wiki.gentoo.org/wiki/GPU_passthrough_with_libvirt_qe...

You can also find countless blog posts and videos on setting up GPU passthrough.

One excellent resource for gaming use-cases in particular is this subreddit: https://www.reddit.com/r/VFIO/

Last thing to note is that your motherboard can make the process easier if it has good IOMMU support. Basically, you want a MB that puts your PCI slot in a separate IOMMU group. You can find examples by searching for “(MB name) IOMMU groups”.