What’s the risk of replying ‘I don’t know’ when asked a question? The questioner may be miffed that you don’t know something that they expect you to know. No big deal. Pretending that you know is a far greater risk. Nowadays, we are expected to have an opinion on many things – politics, religion, defence, climate change, lockdowns etc. The media feed us with opinions.
Remember that when you don’t know or are ignorant, it is foolish to pretend otherwise. Shakespeare said it differently. If you don’t know the answer or don’t have an opinion, say so. If anyone says ‘ you should know’, you can agree with them. ” You’re right. I should know but I don’t”. Or ” I don’t have enough information to form an opinion yet.” Your ego won’t like admitting that you don’t know everything but will get used to the new, less opinionated you.