Probably because while regulatory capture is a real thing, and the FAA did bend for Boeing, the FAA was partly the cause of the MAX disaster. If there had been a small incremental training sub-type certificate program, then Boeing would have trained pilots in how to handle the different pitch moment of the MAX. Instead the type certificate thing led to... well, everything that happened -- not inexorably, no, because Boeing screwed the pooch in many ways, and perhaps they would have found other terrible mistakes to make. But inflexibility at the FAA was -ironically!- a cause. I say ironically precisely because then the FAA relaxed the redundancy requirement and so on.