I think those that have a dependency on Games for Windows Live are screwed, so not Microsoft first party games, but most should? Isn’t it more XP and earlier stuff that has a reputation for being finicky, not DX9/10 stuff?

Anything that depends on Safedisc is also screwed because Microsoft pulled the driver for security reasons. This includes a lot of first-party stuff like Mechwarrior 4 and Freelancer. Really wish they would put those up on GOG!

I think the only game I ever had trouble running on a newer version of Windows was James Bond 007 Nightfire but compatibility mode seemed to work okay. I haven't played heaps of games in the last decade but any issues have been more with getting the right version of the Visual C++ runtime or PhysX (which Steam usually handles for you anyway) rather than the underlying operating system.