I agree with the comment you were replying to. There will always be outliers, but testing prowess in technical problem solving and grit correlates well enough with the job of a software engineer.

The "amazing scientist" maybe was not a good culture fit, or, yes, the interview was botched.

Good candidates are so good that they often enough compensate for bad interviews. Sure it means we sometimes don't hire the best, but that's better IME than sometimes hiring a not so good candiate.