>>5667574
No, he was booted out because he fixated on the realistic military base designs he should have dropped, for focusing on plot and character when that was largely getting axed, and for allegedly underperforming at work.
Some of this was unfair and he was given a raw deal in that sense, for instance he had initially settled on the idea of a large, continuous world without distinct levels and loading screens (as in it would just constantly load and unload the environment as you moved and progressed), based on an expressed whim by Carmack, and then had to throw that out and rethink that once Carmack decided that wasn't practically feasible and they would just be doing individual levels like normal.
The idea of having flying monsters and teleporters was things which DID stick, obviously that wasn't why he was booted, otherwise they would have cut that, so some influences stuck, and some of his levels were repurposed (becoming some of the best, IMO).