and windows is a genetic term for things made of glass in houses, cars and so on, yet I bet you would never try to use that term to describe your Linux distro
We ported a GUI to our 68K based systems that we sold in the '80 and '90s called GWindows without an issue with Microsoft.
XWindows has been around forever.
As the name "Windows" itself is taken, of course you can't use it (unless you are really selling windows).
