"The PGA always suffers from coming too soon after the US and British Opens."
The PGA was played several weeks earlier than usual this year due to the Olympics.
It was only moved two weeks, it's still not much extra time to get enthused about another major tournament. Check the excitement level prior to the tournament compared to the other majors, it's not even close.
And I know the NFL season takes priority on US TV come September, but it still seems a bit lousy to be scheduling golfs majors around another sport. August in the north east is not a good time to be hosting a major and it often does end in a race against time/weather.