As long as there's a market there'll be the manufacture of illegal guns. Money talks bullshit walks and organized crime isn't going to let this opportunity pass them by.
So i guess the most sane solution for the gov't to stop the manufacture and or import of "ghost and illegal guns" is to ban all legal gun owners from owning any firearms period. Makes perfect sense to me.
Besides as past history has shown, banning things that a portion of the public wants has proven to be a great method in keeping the criminals out of the supply chain because as we know, criminals always abide by gov't laws and regulations.