I've boxed most of my life, sparring here and there, and I feel like I'm OK for now.
I wouldn't worry about that until much further down the line. They aren't even allowed to hit each other in the head at that age. They do some light body sparring maybe when they're yellow or green armband. It's just technique, combos, and cardio/fitness right now.
My expectation was never that he'd go pro. Though his coaches have mentioned it (he's taken to it pretty well)!
I feel like head trauma is, understandably, a real concern when you make a career of these kinds of things. But training etc. I would think he'll be OK.
The science is being factored into all of these "sports" now too. For instance, he does soccer as well and they're not allowed or taught to "head" the ball. Because of head trauma.
So as time progresses my hope is the training will be safer in MT as well.