The players are also to blame.
Really, are all those old players going to try and tell me they never had any idea that willingly bashing their heads into things hard hundreds if not countless thousands of times might lead to bad long term consequences, even if nobody, the teams, players, coaches might have known the ultra fine nuances of it? Just by common sense they knew they were taking big risk and took them.
At some point it just needs to be excepted as part of the game's risk and adults with informed consent should do it if they want instead of watering down football into something it's not with still trying to slap the name football on it.