Grid that axe all you want, just not with revisionist BS like that. Duke3D took 2.5 years to launch after DOOM. And then only 5 months after Duke3D landed Quake dropped. Build was fun, but as a technical competition it was no match for what Carmack was doing.
As for hardware, the first useful consumer 3D hardware didn't land for months *after* Quake shipped, when the Verite boards appeared in stores. And Quake supported them very early. And Carmack was also the primary independent champion of Voodoo, and those were the products that grew that market. So if you want to say he failed by missing the PC 3D hardware revolution, then you're arguing that 1) he missed the revolution he was key in making happen, and 2) he doesn't deserve credit for the revolution he did so much to popularize. More bull.
And Unreal always had its own renderer. Why would anyone expect them to drop their homegrown tech and adopt a competitor's? Not every designer jumps engines every 4 months. (Is that you, George?)
Lay blame wherever you want to for iD's modern malaise, but denying their groundbreaking early achievements is just absurd.