It’s been a pain having to use 2 GPUs and switch monitor inputs for GPU passthrough on a VM for gaming.
The ability described in David Edmundosn’s blog and in KWin’s invent wiki could be used to cleanly hand over the GPU to a VM for passthrough, and once the VM is closed, restart Kwin and have all the apps still run in the background all the while.
This would make dual booting a thing of the past, and would be a much nicer user experience for gamers (Some games will never run on Linux\Wine due to anti cheat).