It's not really 'about' videogames though - Quake has just become an extremely useful reference/testbed because it's open source, very well written and easy to

It's not really 'about' videogames though - Quake has just become an extremely useful reference/testbed because it's open source, very well written and easy to port. You see it in experiments and graphics papers all the time. It makes total sense to use it.