Here is the deal, and there is no getting around this, it is not JUST and NFL issue. This started in pee wee, then JR High, High School and College. These are cumulative over years, but they go after the NFL blaming them pretty much solely because of the deep pockets.
If I were the NFL I would now have all Rookies and those getting new contracts, sign an assumption of risk waiver. It is known, you play football, odds are you get CTE. You assume the risk