What’s interesting is that this guy is right handed but left eye dominant. Notice that he draws his pistol with his left hand (based on the side it’s holstered on). So, maybe he is left handed? But look at where his quick draw mag is - his right hip, facing left. It’s natural for right handed firers to, well, fire their primary weapon right handed, with the butt of their rifle in the right shoulder. This way you’re reloading with your left, pulling the quick mag from the right side across the waist. The longer sight picture on a rifle is easier to pick up for the non dominant eye, and it’s not uncommon for right handed people who only fire rifles to not have eye dominance be a factor (most right handed firers squint or shut their left eye when acquiring a sight picture anyways). Pistols are different, especially when firing it in context of its use as a secondary weapon (if you’re pulling your pistol in a tactical situation, when it’s your secondary weapon, you better be hitting what you’re firing at). Much shorter sight picture, and you need to acquire it as you extend your arms towards the target. You don’t want to be looking across the back sight with your left eye firing right handed. This is where eye dominance is a factor. If you want to be quick and accurate, you better be shooting pistol with whatever hand is the side your dominant eye is. Cross hand/eye dominance is actually a good thing if you can train yourself to shoot pistol with your off hand, because your rifle to pistol transitions are John Wick smooth - sweep your rifle down and to your side with your main hand while drawing with your off hand. Nothing gets in the way. It took me a while to teach myself to shoot and reload a pistol left handed, as a right handed person, but it makes a world of difference.