There’s plenty of good reasons to keep a windows device updated and available for use.
Honestly, I prefer that to spinning up a windows VM, especially if your needs include Windows software that interfaces directly with external hardware.
I realize that’s not an option for everyone, but for those who have an extra device available, or can afford a used laptop to keep in a closet, it’s well worth it IMO.
Virtual Box is a Type 2 hypervisor, which means it’s running on top of the OS, and not directly on the hardware.
KVM is a Type 1, which runs directly on the hardware itself.
There are pros and cons to each, and VBOX is a great piece of software, but it is more resource intensive than other options available.