Some obscure title will surely have weird driver, hardware and OS quirks. For example Crazy Machines 2’s physics break down and the fixes didn’t work for me. They use PhysX for their physics engine, before Nvidia acquired it, and it was heavily updated of course and now the puzzles don’t work anymore. Maybe somebody found another solution to it by now, but I haven’t checked it.

I think people misunderstand what “active support” means, yeah. Of course Steam will at least for a time still work on Windows 7/8. It just means they’re sunsetting the testing VMs they’re using. From now on any breakage might happen and not be caught. Or might not happen. They won’t go out of their way to break it though, that’d be extra work for no income.

Because this will happen to Windows 10, 11 and so on as well. And at some point Windows will make breaking changes for some software in perhaps a decade or more, even if only overall very minor. We need and should think about preservation of cultural goods.