No, it’s definitely the graphics and gameplay. The distribution helped, but that wasn’t new - id and Apogee and others had been distributing demo “episodes” of

No, it’s definitely the graphics and gameplay. The distribution helped, but that wasn’t new - id and Apogee and others had been distributing demo “episodes” of their games going back to Commander Keen at least. Doom was a monumental technical achievement when it came out, and if you want some real perspective on that, check out the game that came out just a few weeks earlier and was considered “cutting edge” at the time: “Blake Stone: Aliens of Gold.”