Yes, I misspoke with that sentence. In those days I mostly played on two local courses, and it was a mistake to generalize from such a small sample.
In the 70's, everyone played with blades--pure blades in my recollection--as they were all that was available. So, to play well golfers had to learn how to play these difficult irons, and ball striking would correspondingly improve. I think the current tendency to find ever more forgiving game improvement irons do not help a golfer to improve. Just the opposite, I think.
For what it's worth, in those days I could drive the green on short par 4's with a persimmon wood. Sometimes, anyway. A pinnacle in those days was a rocket.
The thing is, these courses, and their pars, are as they were fifty years ago. It's no coincidence that par remains unchanged on these courses.