Guns don't kill people. It's just a piece of metal or composite with moving parts. Period.

Someone has to put a bullet inside and pull the trigger.

Guns allow people to do he things they can do with hands, sticks, knifes on a longer distance and a bigger scale. That is the difference. But as with sticks, stones and knifes they are just objects lying here or there. Without the interaction of a human they are harmless.

Object aren't problems. The operator CAN be a problem.

Banning legal guns doesn't solve killing as the bad guys in general don't use legal guns. The good guys will be left with sticks and stones whereas the bad guys will still import their "thunder sticks".