The risk of getting hit by a 14-year-old kid is obviously less than the risk of getting hit by one of the hardest-hitting 26-year-olds in the world, but the rewards are also less. Many Hall of Fame-level NFL players have said that the glory, fame, and riches were worth the lifetime of pain, dementia, etc. afterwards. It's not clear that someone who got 10% of the brain damage but 0.0001% of the rewards would say the same thing.