One reason Doom succeeded so well was that it did everything it needed extremely well, and left out anything it didn't need. So it was 3D enough to look cool, had enough lighting to make things spooky, but still ran relatively fast on the hardware available.
Yes, indeed. Doom kind of perfected everything it did. With good enough hardware, it ran fluidly, looked gorgeous and had excellent yet simple and accessible gameplay mechanics. I'm not dissing Doom, it's one of my favourite games ever.
And so is Ultima Underworld... which happened to have almost the HW requirements of Doom but almost 2 years earlier and a lot more complicated gameplay, though.