A question is a demand for a piece of information that matches a given criterion. A "why" question is a demand for an explanation. An explanation is an insight or method that could have been used to predict the thing being explained.

We know that no answer to our question can exist, so it's insane to ask it.

Because there simply is no way of predicting the coming into existence of reality. There were no causes before causality itself.

So maybe the real question is: Why do we feel like there must be a reason for something to be, rather than nothing.