Even the developers I know at Microsoft use Linux or macOS!
It's hard not to look around with your own eyes and notice that you never see anyone using Windows - like I say, even the Microsoft ones!
Do you meet a lot of developers using Windows? What kind of circles is that in?
The games industry is primarily Windows based.
I would generally say that native Windows development is in decline, but it's a long slow decline and it's starting from an incredibly high base.
"a rounding-error of zero" is so wildly incorrect that it is very clear you are in a bubble of sorts.
(It can be different in some teams - e.g. lots of Macs in VSCode - but company-wide that's an exception rather than a rule.)