What if tests are becoming harder and pointless? Do we have evidence that the set of questions asked on exams revolve around the same theme of questions? I re

What if tests are becoming harder and pointless? Do we have evidence that the set of questions asked on exams revolve around the same theme of questions? I remember doing my high school chemistry exams and one of the teachers intentionally set very obscure questions on topics we didn’t cover. We all did poorly and she used to say “students are getting dumber”. That was a decade ago. Turns out when the teacher got replaced and the new one asked questions from material we studied, “students are getting smarter”. ChatGPT and future models are training on entire corpus of available human knowledge including the various high school and college level exam set. So much of exams is pattern matching on existing questions asked from previous exams.