Like any abuse fighting, your goal is not to make guns impossible to get (which is impossible), your goal is to make it as expensive as humanly possible, which

Like any abuse fighting, your goal is not to make guns impossible to get (which is impossible), your goal is to make it as expensive as humanly possible, which decreases how many people have them and increases overall societal safety. Also mobsters get rid of guns that killed people because they can lead to stiffer penalties. So taking legal guns out of circulation and then making strong deterrents for possession of illegal guns does help achieve this aim, you're decreasing the overall supply and driving up their prices.