Athletes can show off their skill in flag football. You think Americans are going to watch that?
The NFL will draw athletes below the caliber of what is seen in the WWE if they don't figure out a solution. Who is going to watch it then.
It's simple economics. If you want talented employees you have to make them attractive offers. What kid is going to choose football and dementia over baseball, basketbal or some other sport and old timers games? How many of their parents are going to let them choose the former?