This article distorts every aspect of the argument.
The long-term concussion history effects in many players will have begun in elementary school football, certainly by high school. It is felt that even if players only made it through college ball and stopped playing, the progression to long-term effects on the brain, if they were destined to occur, will have already been well-established.
Furthermore, as for attempting to minimize the effects of lower body injuries, talk to the post NFL players that have sustained significant football hip, knee or ankle injuries (which would encompass most players before their careers are over) when they were younger. You might be genuinely surprised how many have had major knee or hip or ankle reconstructive surgeries or replacements and/or wheel chairs waiting for them by the time they were 40-50. You might find that they may question their quality of life issues being less debilitating than the very much fewer players afflicted by significant brain effects such as CTE.
If you are going to take one side of the argument or the other, that's fine...........but not on the basis that lower body injuries are temporary or just for one season........and therefore should be a lesser factor in the overall equation when evaluating the entire injury problem.