Earlier quoted context omitted.
Well, my Windows applications from 2000 can still run on Windows 10, without being recompiled, regardless of the UI changes.
Some, not all. And Wine/Proton is (i would say) more compatible with old Windows-Apps then Windows itself, not even talking about dosbox/dosbox-x.
It did plenty of good to OS/2 native applications.
And some is still more than I could say for something compiled in Red Hat Linux (!Enterprise) or Mandrake, to put it in perspective regarding 2000.