"No you wouldn't. You can't stab or club someone who can run faster than you, and you can see off a knife wielder with a chair, pool cue or beer glass (done that, admittedly with a rather large one)."
Sure, anytime a situation turns violent all kinds of things can happen. A 90 year old man can brain a 20 year old tough guy with a lucky shot from a tire iron, but you're a fool if you are betting on him to actually pull it off.
The vast majority of the time, violent human behavior comes from young males. There are clear biological reasons for this and no chance of it changing anytime in the foreseeable future. The young male is physically superior, on aggregate, to any other demographic, so if there are no weapons in play he has a dominant position and can do much damage. Weapons serve as an equalizer here, and the better the weapons involved the closer to equal the contest becomes. The 90 year old man confronted by a 20 year old tough, in other words, has no chance with bare fists, but a very good chance if he has a loaded shotgun. And the tough guy is going to simply back off the moment he sees it, because he knows what it does to that power relationship himself.
So what you do when you remove the weapons is empower the most violent demographic and encourage their worst tendencies. Think about it.