What happened to the source code ? Or was it Diablo 3? I can't remember. I remember they released the symbol files by mistake or something. I was under the Impression that we would be playing Diablo on every toaster in town by now.

It links to https://github.com/diasurgical/devilution. WHich explains it: Climax Studios was contracted to make a Playstation port. And it ended up being shipped with the debug symbols still in the game executable. The pc version also has a lot of debug information still in the game files. So reversing engineering the source was made a lot easier.