Many past fighter's have brain damage, but let's look at current fighter's with signs of brain damage: Broner Tank Davis Chisora Wilder Spence Farmer Rios Ortiz Guerrero D Alexander Quilin Angulo
Most of them do. These guys are a lot more fragile then most would think. There was a UFC fighter not long ago who got brain damage from whiplash being shoved at a weigh-in and had to pull out of his fight.