As I understand it, that is incorrect. It's more like a hypervisor still running in the background. That may have rolled back more and more with recent versions, but in principle the hypervisor can show shit like temperature, voltages and frequency in wrong ways, or delayed to the 'guest', whatever that may be. Actually that was the case, for some time, as some low-level tinkerers and/or overclockers discovered.

Similar to anything running in SMM (System Management Mode) on X86/AMD64 since the times of the 386SL. Be it BIOS, APM, ACPI, UEFI, or whatever.

I repeat: "It's just an illoooshn..." (There is now raw iron/silicon for consumers)