The referenced Philadelphia Inquirer article is why the 14th A. now makes a HUGE difference with respect to how the 2nd A. is interpreted. Regardless that DC (DC v. Heller) cannot make laws that infringe on gun rights, if it weren’t for the 14th A., Philadelphia could do so. This is because the Founders decided that federal BoR did not apply to the states. And the 14th A. not only changed the scope of the 2nd A. to include the states, but 14th A. lawmakers also clarified that the 2nd A. protects personal rights.
Not the issue here. No local gov't can make a gun law. That's the PA state law.