If there's a big enough bias, the questions become entirely about finding that bias. And on 90% of cases the systems design questions are about something they designed in-house, and they often don't have a lot of experience as well.

Also: if there's limited knowledge on the interviewer side, an incorrect answer to a question might throw off a more experienced candidate.

It's no big deal but it becomes more about reading the room and knowing the company/interviewers than being honest in what you would do. People don't want to hear that their pet solution is not the best. Of course you still need to know the tech and explain it all.