Games in 1995 were targeting DOS and Windows 95, not Windows NT. They were doing so because that's what was on the majority of consumer PCs, and their objective was to sell games. People selecting a server-side OS and dev tools didn't have to worry about what ran on end user machines.

If you look hard enough, you'll find exceptions of course. I think Ebay was built on Windows servers, but in the late 1990s, building your web startup on Windows was a sign that your technical leadership had bad taste and a competitor would run circles around you.