Do you really think people younger than 30 won’t be using Windows in school or at home?
They will use it, but they don’t know it’s Windows or what an OS is. They’ll just say it’s a Microsoft computer or PC. Or “not Apple”. Maybe even Android.
I mean, there exist and have always existed people who’ve never used it at home. And there exist and (ever since it came out) have existed people who have.
What I’ve tried to express is that there’s a small band where not having used it is unusual and surprising, and that isn’t the case anymore. I still think the majority of people have used Windows at least a handful of times but hearing that somebody hasn’t no longer produces a “how could anyone” sort of response.
But, I also think there’s enough leeway in the idea of “using a tool” to not be surprised that somebody doesn’t count a one-off use of notepad. And I think there must exist at least some people who really never used notepad.
Nowadays I only assume someone between, like, 30 and 50 will inherently have to have used Windows at some point. Outside that range, you might get graybeards who were around before Windows, or younger folks who only ever used smartphones.
Anyway, all that rambling is to say, I’d put it in the “most but not shocking to hear otherwise” category.