If they believe in Santa Claus, they are too young- that handles a bunch of this discussion right out of the gate. If they can’t safely carry the weapon, they are too young. If they can’t load, aim, or operate it safely on their own, they are too young. If they don’t understand death, they are too young.
While development is a spectrum, and people are allowed to raise their children as they see fit- we have collectively decided that there are certain things requiring a certain age or associated level of maturity typically attained by then, and certain ways of raising children that are unacceptable to the point of being illegal. And to be perfectly blunt, I don’t trust the majority of people to responsibly raise a child, let alone teaching them how to safely and ethically hunt.
There are age restrictions on driving a vehicle, for example. Age restrictions on holding a job. We collectively decided that hunters education needed to be mandatory. And in some states, age restrictions on big game hunting. A big part of that is the safety regarding using a rifle.
With that said- Having a 6 year old shooting a deer is insane. 12 is a decent age. 10 is highly variable. So to be safe- 12. Small game? Fine. Small calibers, limited range, less pressure to fill a tag and do something stupid. Marching your kid out to a heated stand to pull the trigger on a crossbow you pulled back, set into a rest, had to click off the safety, and told them where to shoot, is more about stroking your own ego rather than responsibly raising your child to be an ethical hunter. I see it as a worse version of a child beauty pageant.
It is appalling what these rednecks think is appropriate, and I’m against it- for the good of the kids, and the good of the sport.