You nailed the qualitative difference, Eri. A gun is a "standoff weapon", a device for remote killing that depersonalizes killing and shields the conscience from the reality of the deed.

The problem's exacerbated by the portrayal of gun violence in films and TV. People who learn about death by gunshot that way imagine that a gun is a device for making people politely and quietly fall down, apparently painlessly, as if they're sleeping and not actually dead.

While it's trivially correct that guns don't kill people, people kill people, the problem is that guns make it too damn easy to kill. Common sense alone is sufficient to tell a rational person (non-gun-fetishist) that an abundance of guns will inevitably lead to an abundance of killing. The facts bear that out.