Your point is valid. People in general don't recognize the value of a top running game in the NFL. When you have it, it does several things. It allows you to control the pace of the game, wears the front 7 on the opponent's defense down, and improves the passing game because more defenders are focused against the run thereby freeing up more opportunities in the passing game.
If you want a perfect example of exactly what you're referring to look no further than Bart Starr. He was a superior game manager, who rode the running game, and used the pass to exploit the weaknesses created by the running game. He didn't try to reach outside himself to do Herculean things on the field, just used the tools at his disposal. When you have a running back like Jimmy Taylor, and the defense has to worry about stopping him, you will spot weaknesses across the line from you.
Just looking at the history of the Super Bowl you can see an awful lot of QBs on that list that weren't consistently leading the league in any category. Yes, there are exceptions, but like I said, they are exceptions.
