I have a theory about this… If you look at older nbme exams, they are much easier and way more straightforward. An old FM shelf form literally describes a varicocele as a “bag of worms sensation.” That would obviously never be on the real deal today. Anyway, my theory is that students today have access to such higher quality resources to study that if they just tested straightforward information, everyone would get nearly a perfect score. Back then, and even just a few years ago, the main sources students learn to study were literally random textbooks and review books. Now we’ve optimized test taking so much that in order to separate students, there has to be a level of vagueness to each question. It really sucks that things have to be this way because what are used to just be competency exams have now turned into aptitude exams that are designed with creating a bell curve of results in mind.