It is of course impossible to compare players of different eras.
But I look at body types, body shapes, weights of different eras. Guys today train year round. The science is so much better now.
Here is a comparison you can make (different sport). But there is very little difference from 40 years ago to today in kicking an NFL field goal.
Jan Stenerud is an NFL Hall of Fame kicker. One of the first soccer style kickers, he was so good that he was voted into the hall of fame.
For his career, he was a 67% fg kicker.
Today, a 67% NFL kicker would be cut by Thanksgiving.