The biggest part of gun laws is checking for responsible ownership. You are allowed to get hunting guns in most of the countries that the right says “ban guns”. They just have common sense checks, like do you have training at a shooting range, do you understand gun safety, do you have a gun safe, are you not a psychopath prone to fits of violence? Your upbringing wouldn’t be any different because your parents were responsible and would have passed all those checks.
This is about not giving a gun to every dumbass yahoo that stumbles into a store. The household this kid grew up in obviously wasn’t responsible because this kid has unsupervised access to a gun.