The Importance of Technique in Training

I wonder if some of the talent that we see today is a result of just a better format of training. Technique is different now in boxing, in wrestling, in jujitsu,. In UFC, mixed martial arts in general, the technique is higher. People have learned from other mistakes, things have piled on in a more, let's say beneficial way before those who know it. Would you say the World War II Marine should be tougher or not as tough as today's Marine?