That way of assuming a PC uses Windows is from the era where no better OS existed on Personal Computers. Or when it was the only option, but not anymore.
Nowadays there's Linux (all x86 distro's), Solaris (x86), MacOS (x86), and a plethora of great alternatives to Windows.
Myself had never ever related a PC with Windows, as they are totally two different subjects. One related to hardware and the other with software, and they are not "married" by no means. Even though Microsoft would be happy if that was law.
Nowadays there's Linux (all x86 distro's), Solaris (x86), MacOS (x86), and a plethora of great alternatives to Windows.
Myself had never ever related a PC with Windows, as they are totally two different subjects. One related to hardware and the other with software, and they are not "married" by no means. Even though Microsoft would be happy if that was law.