PC Gaming

It solves almost everything?

I guess you don't understand the benefit of putting all the shady Microsoft shit in its own dirty polluted sandbox (or individual sandboxes) where it can't spy on anything besides the other stuff in its sandbox that is already tainted and at most it may find a way to spy on the stuff you give it implicit permission to while you do whatever work you need to do with it. Meanwhile your main OS which hopefully does at least 90% of what you actually need to do on a daily basis, and does all the stuff that is actually important to you and happens to be none of Microsoft's business, is safely running the actual show and remains completely under your control and authority, private and spyware-free. If you can't completely get rid of Windows from your life (and some people still feel like they can't for whatever reason), you can at least limit your exposure massively and turn it into practically a non-issue. Compartmentalization is a very effective way of dealing with nasty untrusted software.

When you get that shit locked down tight enough you can run straight-up viruses and rootkits with no concerns at all. You can see what they do, or try to do, and when they're finished doing it, just casually delete them. Some people do. For research. In fact it's so common that a lot of viruses or rootkits go out of their way to try to detect that they're on a VM and refuse to activate if they think they are, there's a whole arms race of researchers trying to make the VM look more realistic so the virus will still trigger. Even the viruses know your VM is probably just fucking with them. Windows, thankfully, isn't quite that bad, and programs written for it will run quite happily in a VM or other virtual environment and let you do whatever you want to do with them, quite safely and subject to your complete authority over them that a VM or other simulated environment can provide.