Thing is, DTW, procedural creation of dungeons is nothing new. Diablo did it way back when.
However your point about innovation still stands.
Innovation is something that changes the game, so to speak, and affects it for years to come. Like the joypad, when it came onto the scene with the NES, very few people actually batted an eye, but it's now the industry standard control system for all consoles.
QWERTY keyboards, the Mouse controller, all these things are innovations that we now take for granted, but literally changed the landscape of gaming.
Software speaking, one major innovation was from GTA 3: Adaptive AI. Until then every reaction done by non-player characters had to be scripted, and then looped. But GTA 3 made it so that the NPCs had a 'routine' (a rather simple loop) but whenever a threat came close, like a barreling car with a player at the wheel hell bent on racking up their hooker killing score, the immediately tried to avoid 'death' by running away from the threat. Until then, that was unheard of. But did we notice it in between our binges of Hooker Heals and Kills, and avoiding the cops as we try to jump over the chopper using the mound of cars and corpses as a ramp? Nope. But since then, people have used that sort of coding. THAT'S innovation.