Earlier quoted context omitted.
That's true, but it's a bit late for that, at least in the US.
Our gun industry produces more than 11 million guns a year. Sure, many of those wind up in Mexico and Central America via the drug trade, but that's still a lot of supply being sustained through the system. Guns wear out, simply cutting production would do a lot to reduce the number of guns in the system (outlaw or not).
We'd save more lives by forcing car manufacturers to install ML based drunk detection systems in the driver seat.