Let us suppose that all physics is solved, as you say. Then, why should we even ponder the "why" if there is no way of knowing the correct answer? If we cannot

Let us suppose that all physics is solved, as you say. Then, why should we even ponder the "why" if there is no way of knowing the correct answer? If we cannot know this answer, then the "why" is in fact unimportant to divine, a waste of time. To explain further: You are saying that everything observable is understood. So, this means that the only evidence for "why" is the equations themselves. "Why" is the cause or intention underlying something. However, there are infinite explanations how any piece of evidence arose. If all that we have is the evidence, without knowing the laws governing the universe it was produced in, then there is no way of deriving intention, i.e. "why" the evidence exists.