To quote Homer, who as far as I'm concerned is a much greater source of wisdom than Ben Shapiro, "The sword itself incites to acts of violence".
Ben Shapiro is clearly very proud of how clever he thinks he is, because he keeps telling us how clever he is; and to be fair to him, there are enough other people who agree. The problem - well, just one of several - with Ben Shapiro is that no matter how smart he is, what his intelligence is directed at is creating easily digestible snippets and slogans for right wingers mostly of much more modest intelligence - in effect, PR. Again to be fair to him, he's good at it. But it's not analysis, it's not deep, insightful, or in respects potentially honest.
Superficially, yes, not having guns does not solve violence. However, Homer's quote recognises that if you have the capability to resolve a problem with violence, you will be more likely to use that capability when you encounter the problem. (It's not until we got to nuclear weapons and the capability becoming more of a problem than the problems it solved that changed.) With a lesser capability, even if violence is employed, I suspect most people would prefer a broken jaw to a bullet through the skull.
In particular, I think there's strong element to crime and violence (including suicide) that is impulsive: the idea that all violence is planned and premeditated is obvious bunk. Not having ready access to highly lethal weapons means when the impulse strikes, it either cannot be expressed or the expression is vastly less severe.