

It’s relatively trivial, you just need to write a kernel module. You’d just need/want to make it gpl so everything it does is fully audited and transparent. That’s not a problem, is it? Right?
From a technical standpoint, you could argue that someone could create a fork of the kernel that spoofs the interface that the anticheat uses to make it ignore things. You can, of course, also do something similar in Windows, but security theatre never let practicality get in the way.
I don’t think so, Valve already have their hands full with one translation layer and probably don’t want to add another layer on top of it.
I also wouldn’t be surprised if battery life ends up being worse through the hypothetical vm. It still has to do the same amount of work after all.