People that hunt and shoot guns their whole lives do not commit suicide at high levels. This is what I am basing my statements on. Basically half the people I know in the US fall in to this category.
People that hunt and shoot guns their whole lives don't shoot guns their whole lives. They shoot guns a few times when hunting and then a lot of times at the range but at a leisurely pace. This is like comparing a package delivery guy who likes jogging to an Olympic athlete.
You'd be surprised how much time SOFs im general spend lying in a bush, peeing on bottles and radioing in updates. Although US SOFs may have been doing it less than others during GWOT. Not everything is DA.
(That doesn't change your general point though, and SOF training is extremely rigorous and demanding and does include a lot of shooting. But not all day every day.)
A hunter (I am one) might shoot a dozen rounds to zero in a rifle, or a hundred shells at a clay range. Actually hunting is never more than a handful of rifle rounds or a few dozen shells.
An M4 (the only carbine I can think of in use by the military) is already a step down in boom as a 5.56mm; adding a suppressor makes that even less so. It’s like shooting a .22 at that point. As to SMGs, they’re all small caliber – 9mm, .45, 5.7mm…
I'm saying that a SEAL shooting a suppressed SMG feels nothing after dumping magazine after magazine downrange. There's no way this is causing concussions.
Grandpa's 30-06 will rattle your fillings a little bit after one round - still probably doesn't result in TBI.
SCAR-H, M14 EBR, M249 SAWs and M240 all shoot 7.52mm x 51mm NATO (compatible with .308 but slightly different chamber pressures)
As I said, we don't if calibers below .50 cause significant damage when shooting in excessive amounts. Trying to figure it as a layman is useless. It's better to show epistemic humility than try to assert one way or another.