First: violence was a lot worse before, so what makes the author think going back in time with weapons is actually good?
Second: that guns allow the weak to be as threatening as the strong is considered a feature by many people; an equalizing force. As the saying goes: "God made men, Sam Colt made them equal." The idea that you can find vulnerable people and exploit them without fear is a big driver of violence -- but if everyone must fear violence coming back at them, that's a pacifying force.
Third, the author goes on about the sustainability of guns. But arrows are a lot bigger and more expensive, so I question the idea that they'd be made sustainably. "Artisanal" means wood, I suppose, and that could be much more problematic than a few factories cranking out bullets. People would reuse arrows more, but there are also a lot more people today so that would really involve some kind of industrial process and I doubt it comes out as a net advantage.
Even when it comes to public safety, I'm not quite sure it's a win. We are pretty safe most places, and in the US, violence is mostly local to known areas.