I don’t think it makes sense to permanently stop people from posting certain questions. Answers to questions are affected by who is in the community, how the question is asked, and recent world events. Over time, those factors change.

Take “What’s your favourite ice cream?” for example: would you get the same responses today as you would’ve gotten last year, 5 years ago, etc.? Maybe some company just released a new hit ice cream flavour that’s trending on social media and you’ll get a lot of answers talking about that. Maybe there’s vanilla shortage and all the boring vanilla folks are forced to try other flavours. Or maybe the vegan community finds the thread and submits all their much better ice cream flavours (shout out to coconut milk ice cream).

If you really want to avoid the question getting asked over and over again to the point where everyone is tired of it, I think it would be better to set a minimum time limit before a question can be re-asked to make sure the answers will be different enough since the last time it was asked.