This was always the claim, yes. And much like how these days people complain about getting rejected for slipping up on a leetcode problem in a minor way, back

This was always the claim, yes. And much like how these days people complain about getting rejected for slipping up on a leetcode problem in a minor way, back then there were plenty of stories of interviewers treating these problems as a black & white problem where you were expected to just know the answer. To be clear, the problem wasn't the question. It was the interviewer asking the question.