No, you have it backwards. The Nunn decision explicitly upheld bans on concealable weapons.
But over turned the law as there was no provision for open carry. Can't have both as they violate RKBA. Bans on CC are fine as they fall under "regulation". But then you can't ban open carry.
Nor can the imposition of a number of fines to exercise a Right be considered legal either. Any number of poll taxes, preventing certain peoples from voting, have been shot down numerous times.