In order to prove that discovering calculus got harder, you would obviously need to show that the population of people who could discover it but didn't have pri

In order to prove that discovering calculus got harder, you would obviously need to show that the population of people who could discover it but didn't have prior knowledge of it was at least as large as when it was discovered. In addition, in order for there to be published (or even submitted) papers, you would need those people to not only not have any prior knowledge but to not encourter anyone with a highschool understanding of calculus in the review and publishing process. As that is equally obviously not the case, I repeat; that's not how that works.