You could pretty much say the same thing about Carmack. He just kept making the same doom and quake game over and over with better and better tech. Carmack's space company venture didn't work out, then he went to work at Oculus where he couldn't get anyone to listen to him and got frustrated and left. Now he's at some AI startup.

In some ways Romero actually saved ID software and made everyone a ton of money by working out licensing deals for their game engines. Carmack wouldn't be able to continue to work on his tech and hire Abrash (who optimized Carmack's code) without the money coming out of these deals so he unfairly complained that Romero wasn't pulling his weight for the current project and treated him like crap until he got fed up and left.