Humans are not rational brains riding round in a sort of meat carriage, we are animals and our whole body (and social setting) adds up to who we are. Physical conflict is part of human life - specifically a proportion of young men are predisposed to physical rivalry. Taking options to express this away does not remove the predisposition, it merely shifts it to other outlets which may be much less constrained and much less positive.

Behavioral issues in young males without a physical outlet for aggression?

I'm not sure what type of childhood you had, but the idea the soccer and high school football is going to give a person brain damage is goofy simply based on the current and available data.

If you simply look at that massive number of males that played high school football in, for example, the 1970s, we would have epidemic levels of serious brain issues in an enormous percentage of the the male population. We would be talking about 10s of millions of people with serious brain damage. For example, in 2016, over 1,000,000 young males played high school football. I think it is safe to say that men between 50 and 60 years old do not all have serious brain issues. Even though a very high percentage of those men played high school football.

With that said, we have much lower numbers of men that have played division 1 college football and an even smaller number that played more than a few years in the NFL. In the NFL, the average career length is only 3 years. The speed, size, and strength increases dramatically at that level and we are seeing data that could indicate real issues with brain injury.

It is strange to see people on a site like HN that do not even have a basic understanding of data driven concusions.