Reasons:
Could you help with references for these please? @HulaHoop
There's been research showing that trying to hide CPU information in a virtualizer is futile.
I can't find papers to that effect. That's based on my intuition that someone can just benchmark the CPU in a VM to figure out what model they're running on.
With full emulation it may be possible to conceal all aspects about a CPU from the guest code at expense of performance.
The opposite however is true. It's impossible to hide the fact someone is running under a hypervisor.
There's been a Xen issue where hiding CPU information lead to a security issue.
Dug through their CVE database with no success. Search results are equally useless.
spectre / meltdown defenses may depend on easy CPU detection.
https://www.berrange.com/posts/2018/06/29/cpu-model-configuration-for-qemu-kvm-on-x86-hosts/