In sports there seems to be a natural evolution towards more specialization and power (through fitness), both of which invariably favor the defense. You can try and help the offense by juicing the ball, making rules to protect the quarterback, and adding a three point line, but you’re fighting an uphill battle. The folks on the other side are going to figure out how to stop it. People specializing in defense just seem to be more tenacious, creative, and innovative. I guess it’s by necessity.