a) the inflection point is in the high 30s. Further $\int_{40}^{50} f(x) dx > \int_{20}^{30} f(x) dx$.

b) true there is no breakdown but I would expect the exact opposite as fields get harder. More context requires more training and familiarity, which I would expect to increase age.

My point is that I think there's a bias in the field towards the youth narrative but the majority of discovery, even in physics, happens at a later age.