

Windows is only 12% of Microsoft’s revenue, and between Mac, Linux and ChromeOS, it really doesn’t have a monopoly anymore on desktop (about 70%). On top of that, desktop usage in general is decreasing, and is already less than 50% of all web traffic.
What I’m saying is that I think it’s safe to say something else will likely “kill” Windows long before Linux ever becomes a serious threat to it.
I had the same thought (For example office runs on other operating systems but is still largely windows) but 80% is likely generous: