As to ensuring adequate gun training for individuals seeking CCW and open carry, simply equate it to passing both driver’s education and DMV requirements in order to obtain whatever class of driver’s license. In whatever case there are many other aspects to proper gun handling than simply loading a magazine or bullets into a handgun.
Self-defense and bearing arms is a right, not a privilege.
Various states have no required training or permits needed for either open carrying or concealed carrying, and the sky hasn't fallen.