Football is not doomed because of concussions. It will take a hit and dip but will rebound to stay at the top in the US and grow worldwide. Other sports just like you said also have injury problems. Because the NFL is so rich it is a target for people sueing over concussiions. Soccor and hockey will eventually fell this same thing. Kids still love football and will continue to play. With kids in small poor areas see sports as a way out, there will always be kids playing.