Earlier quoted context omitted.
On the contrary, the cheap solution is "assume there's a way to make guns hard to get in America. See, isn't that better?" Yes, maybe it would be better, but you assumed away the hard part. There are already 300 million guns in America, and a deeply entrenched culture in favor of keeping them. That is the initial condition we have to work with. Saying "just be more like country X" isn't a solution at all.
Totally true, one solution though could be to pay people to turn in guns, this won't work in practice probably though.
Keep in mind that you wouldn't need to collect every single gun. You just need to shut off the supply and make the black market ones difficult to find.