Rugby has a massive problem. There are more and more ex-pro players with this sort of issue in their 30s and early 40s, and I don't think the news is going to stop (Steve Thompson, Alix Popham and a whole lot of others took the rugby authorities to court not that long ago -
https://www.theguardian.com/sport/2020/dec/08/steve-thompson-former-rugby-union-players-dementia-landmark-legal-case ). It's not just about concussion, though that is a problem, especially for professionals and aspiring professionals playing in his era (there's an old football joke about a physio telling a coach that the player needs to come off because he doesn't know who he is, and the coach saying "tell him he's Pele and get him back on there"). They are trying much harder to mitigate concussion problems these days with return-to-play protocols and such, but the fundamental truth is that collision sports like rugby (both codes), American Football, ice hockey, etc. are not going to be able to remove those risks.
The research in American Football indicates that repeated sub concussive impacts are a significant risk in the development of CTE, and it was much harder to define where the risk was and how to mitigate it. Pretty much every tackle will cause such an impact, and much of the ruck clearing stuff too, so anyone who played in the back row and racked up high tackle counts should be assessed for this sort of thing IMO.
Football Associations in various countries have removed deliberate heading from the youth game, and more countries are looking into it. I think they should focus almost exclusively on footsal until teenage years, removing all incentive to head the ball and driving better technique. Though it won't stop a stray elbow, which is the only thing I remember making me see stars as a football player.
