And that's assuming running under X.Org.
As for Win32, if the application didn't do stupid things like setting bitflags that were "reserved for future use", things apparently work without recompile for basic GUI from 1.01 to Windows 10.
The problem is that a lot of software... disregarded the specs. Including infamously using "reserved for future use" areas of bitfields, which for example caused a lot of app crashes during early days of Windows 95 (where certain common API gained a new flag that was not compatible with previous flags, which worked fine so long as you didn't set them concurrently - which all properly written applications avoided.)
I run a lot of older software, especially (though not only) games and i often have to do such workarounds like wrapper or replacement libs. I've also tried running older stuff on Linux (e.g. i have a collection of Linux game demos from the late 90s to early 2000s) and while most stuff run, you do need to find and install a bunch of missing libraries and wrappers (e.g. for OSS support).