Earlier quoted context omitted.
I don't think pursuing a career in academia was what he had in mind when he said 'do mathematics'. In fact he said specifically: >Teaching mathematics shouldn’t be about sending everybody to a Ph.D. program. That’s a very narrow view of what it means to do mathematics.
Doing serious research level mathematics (or any other science for that matter) is almost impossible outside academia. Doing serious work is hard and mentally draining. Mere mortals can't motivate themselves to do it unless the incentives align just right (i.e. being in academia). Also it takes all your time so forget about it if you have another job. I know this from personal experience. After I joined industry I th…
For instance, compute the fibbonacci numbers modulo the square of a prime and compare to modulo a prime. Are there numbers where the first zero appears at the same point? We don't know.
I'm not saying the problem is easy. I'm saying one can make some progress without much theory.