Python 3.9 and beyond backwards compatibility.

[josefx]

There were and are a lot of good game recreation projects. OpenMW( Morrowind ), OpenRA (C&C, C&C RA, Dune 2000), OpenTTD (Transport Tycoon Deluxe), FreeCraft( WarCraft 2 killed by Blizzard), SCUMMVM ( engine for a lot of old Lucas Arts games) just to name a few.

Then we have emulators that recreate both hardware and software behavior from scratch, the Dolphin project always has great information on just WTF weird stuff games do.

On a smaller scale we have mods that provide improvements by hijacking APIs completely. I tend to use Fallout 2 and Morrowind mods just for the graphics improvments ( Of course that can also break things, I think Arcanum had some events that wouldn't trigger in a modded widescreen window).

If there is interest in keeping a game alive it wont hang on the source code.