It's a career limiting move in the same sense that my career as a doctor is limited by the fact that I didn't choose to go to medical school. There's no evidence that any of his opportunities outside of making violent shooters have been limited. If he wants to turn down those opportunities then props to him for standing up for something in a way that actually impacts his bottom line. Whether you agree or disagree with his reasons for doing it, this should be applauded. We just shouldn't pretend that he's being persecuted for his choice. He's not a whistle blower that's exposing a conspiracy. People like violent FPS games, they buy them, studios make more of them. That's all there is to it.

Now if you want a conspiracy, you should be looking at gaming addiction and how studios are explicitly engineering games to keep people coming back and spending money. That's where you'll find the real shady stuff.