I would suggest that you haven't read Miller very closely. It is pretty clear that had anyone been present to represent Miller and give evidence that a short barreled shotgun was indeed a suitable militia weapon, the Court would have found that Miller had a right to possess it. The Court said that there was - no evidence before the Court - because Miller was dead and his lawyer didn't bother to show up.
It wasn't eactly wrongly decided. The lawyers for the defendant (Miller) never showed up to offer arguments. Therefore the Government won by default. Not exactly a stellar moment in the annals of USSC history.
Miller was not wrongly decided. Have you ever actually read it? And read the background of the case so you understood what the SC decision was?
In a nutshell, the SC ruled that if the gun in question had any legitimate military use, then the convicted persons had a right to own and bear it. The gun in question was a sawed off shotgun; the convicts were not represented at the SC hearing (one had died, the other had plea-bargained down to a small fine), so no one presented any information to the SC about the military utility of the gun. The SC REMANDED the case to the lower court for a finding of fact on the military utility of the gun (easily provable that sawed-off shotguns HAD been employed in military uses, BTW), but the case was moot for the aforementioned reasons, so there was never any further proceeding in the lower court.