>>513876331 (OP)Because they come from total shitholes and most of them are wrestling and fighting since an early age as pretty much the only out?
That's like asking why jamaicans are good at running, sure some of it might be genetic, but it's also the fact that literally everyone does it, it's cultural, they are all pushed to do it from an early age and then best rise to the top.
Why would any sane european parent for example put his child in combat sports as an all-in career choice? They don't. They have options.
I'm sure we would have more elite white fighters if the only way of making it for us was: become a great fighter or be be poor for life worrying about when's the next meal is going to be.