@EdBoatConnoisseur @BigDuck @WashedOutGundamPilot I do think there is a factor of the standards of grading became easier over the decades, as I recall one my uncles mentioning that expectations for grading were not the same, with Bs and Cs being not too bad where now As are expected.
Also, look at the material taught over a hundred years ago and see how much more difficult it was. Grades may be higher, but that does not mean anyone is smarter.