In the current interview structure, I don't think that's inherently a bad policy. It forces interviewers to develop new unique questions and hopefully, while doing so, consider the cognative time and complexity the solution took them before deciding to hand it to an interviewee.

This also discourages overly complex or overly familiarized questions. If the question is too complex, chances are it will end up posted online soon after, penalizing the interviewer in time cost. If a new question is recycled frequently, it will also likely end up online at some point and penalize interviewers from using questions they're overly familiar/biased in assessment to based on their own rote learning.