40 years ago there were no computer science classes. Electrical engineering was more about laying cable than designing ASICS. Human Resources Management was called "Personnel." Imagine how much more history has to be learned now versus 40 years ago? Every specialty you can think of, with the exception of buggy-whip making, has advanced exponentially in terms of technology, terminology, and depth of knowledge. Is the subject matter easier today than it was 40 years ago? Absolutely not. Are teachers grading on an easier curve? Probably. All in all, I think it's a wash.
I talked to a science teacher at my old high school a few years ago, he started teaching the same year I graduated. I asked him how things had changed in the last 20 years, and he told me that he finishes up the year now, at about the place that he used to begin.
I hire a number of young adults every year. When I read their job applications it is obvious that spelling and grammar are a lost art with many of today's youth. It is equally apparent that a strong work ethic is a thing of the past as well.