There is probably a person with the power to inject the GPL into the license agreement, and if it does, it would destroy Microsoft as they'd now be legally required to cough up the source code for Windows
Is this a real window? If so the guy who designed it needs to be promoted. A useless fucking image takes more space than text view containing the longest wall of text known to man.
Windows contains a lot of stuff proprietarily licensed to Microsoft, so they don't have an option to turn all of it into free software even if they wanted to.