Agreed with all of this, well put. I’d like to add though that we don’t do math just because we anticipate there will be some practical utility in a different field down the line. Mathematics isn’t merely a prerequisite for engineering. Does it not suffice that we study math for the sake of it?

The Mersenne primes for example are a delightful little mathematical object. IMO they are immediately curious and interesting. I am very grateful that we continue to make progress in understanding them.