"If the heat shield breaks then I will die" is the exact situation for the astronauts, and yet we still have astronauts.

In fact it's worse for the astronauts, because in this hypothetical only the heat shield failing will condemn the POs to death, whereas any critical part failing kills the astronauts

Yes, it's a much sexier job than project manager, but clearly there are some people, in some circumstances, that would accept it.