From CATO:

While Heller clarified that the Second Amendment secures an individual right, the ruling left many questions about the scope of that right unanswered. Since then, several courts have made clear that they plan to take only as much from Heller as they absolutely have to.

Since Heller struck down D.C.’s ban on functional firearms in the home, recalcitrant courts pretend that the Second Amendment is limited to the right to keep arms and that legislatures can for very little (or no) reason to ignore the right to bear them outside the home.