I would further that by saying it depends on the child and their family.
I am the daughter of a now retired cop. He taught me how to clean my own rifle and shoot at 2 years. We had extensive gun safety and care training, especially me, because I was curious enough to probably find one hidden in the house. We were too poor for a gun safe at the time, so us kids just learned better.
Now I wasn't taught any fighting or holds because my dad was afraid we would use them on each other. I remember my brother jumping on my back in immitation of a cartoon. I just slammed him against the wall of the hallway, got my feet propped on the other wall, and pushed until he tapped out. My older sister wasn't so smart.
My boyfriend wrestled with his brother sure. They were allowed to watch many things they probably shouldn't have and imitated wrestling moves on each other. But they never hurt each other the way my siblings and I did even though we were very
sheltered in our media exposure.
When it comes to my son, violence of any kind is a lesson. Batman gets to drop bad guys because he's freaking Batman. I've promised he can study martial arts if he is older and keeps his grades and chores together. He sees me shoot and box, but he knows these are responsibilities that are earned, not just games.
I hate the slapstick in most cartoons because it trivializes violence, removes a context, and makes it all fun and games.