My two cents on this "math is solved" and "maybe we lose cryptography" question (not that anyone asked of course).
The questions are the important part, I think. What was the inspiration that led to the question which then ultimately created the answer? Having answers to old questions is very nice, but more importantly I think we just need to now use that knowledge to ask better questions.
Don't be a doomer, ask bigger questions now that we have more powerful tools to help answer them. Don't let answers to old questions extinguish the creative spark, if you will.