Real, true mathematics. Constraint solving. Probabilistic calculations and algorithms. Calculations of the limits of functions (property testing kind of does that but not really).
Parallel processing of complex graphs – just one strong innovation here can make most compilers on the planet 6x faster.
There are many examples.
I’m not a mathematician. But nowadays I wish I was. Math has a lot of stuff for us to learn from. Modern programming reinvents wheels and tears them apart on a regular basis.
I feel that we can do so much better.