Try to find some matches and watch them. You will be shocked at the level of football. Indeed, the state of the pitch, the ball the shoes, contributed to a great level to the difference between then and now, but there was a difference, and a huge one. Pure talents like Platini and Maradona were great, but the rest were weaker than their today's counterparts.
Another reason for all this was that 3 foreigners rule. Not a chance back then to create this City, or Ronaldo's Real. No mixture of football cultures where one could borrow the best from the other. The moment they allowed more than 3 foreigners in the starting XI in Serie A, La Liga, EPL, Bundesliga, football became better.
Then it reached its zenith, and it became way too open. Overfilling teams with athletic, but not too talented players from all over the World, and sacrificing skill for athleticism is football's downfall imo.