That stuff has very little to do with 90% of academia math. Also, if you specialized and are interested in a certain field of math, the barrier to switch to another field is enormous. On the other hand, 90% of the applied mathematics done in industry is much, much simpler, and very often a trivialized version of what you do in academia, so one could imagine switching to be possible, but what's the joy of doing that?

(I have a MS in Math, my field was algebraic geometry. I considered a career in math research, but the industry was paying too well for it to be a reasonable)