If Wolfenstein 3D is the equivalent of giving birth to the First Person Shooter genre, then DOOM is when the doc takes the baby, smacks its bottom, and makes it cry out to make sure its alive and well.
I grew up during the golden age of DOS gaming, and I remember both titles fondly, but back then, Wolf 3D felt just like a fun action game. It didn't give off an 'OMG! THIS IS THE FUTURE OF GAMING!' vibe - it just felt like a fun violent nazi-killing game. And despite its great 3D feel, it still felt so fake with all the same looking walls, hallways, and square rooms.
When DOOM was released, the levels came to life with two simple advancements - platform heights and angled walls. And the difference it made to gameplay was like night and day. The moment someone tried DOOM for the first time, they stopped playing Wolf3D. You just couldn't compare them. And for this reason, IMHO, the real birth of FPS gaming began with DOOM.
9/10