Feels like we're missing a piece of the puzzle in this story. Maybe something else happened over that year? Politics? The story starts as you'd expect. Accidents happen. Support. Returning to duty. What went wrong?
So they fire the guy, and promote someone else that can be relied on to say that the F-35 has no more defects than any other plane had at this point in the program, and we can trust the US military industrial complex to deliver the F-47 in a similar fashion.
At the same time, you send a message: eject when your plane is misbehaving and you'll end your career. Sure, there's a risk that someone won't eject when they should, but there's also a chance that you'll be able to cover up another malfunction when the pilot nurses the plane back to base.
Did Pizzo say anything disparaging about the F-35? I doubt it. But when you've got billions of dollars of revenue/potential embarrassment on the line, you don't take chances.