Professional wrestling actually has a high rate of brain and other bodily injury due to the nature of the stunts I'd imagine Luche Libre would be similar, just because it's staged doesn't mean it's not without risks. While I don't know about Rugby, I know there are concerns about CTE in soccer in players who have a tendency to head the ball. As for other "violent" sports, Boxing is a beloved sport throughout the world, MMA is gaining popularity, and countries like Japan and Russia have combat sports such as Judo and Sambo respectively. I hope you're right about football for pewee, high school, and college players, but talking to parents of grade school and high school kids? They wanna see rules changed for the sake of safety, but they still want "traditional football." It's crazy yo.