No, I don't see "a trap". Hopefully the SC will finally rule.
By the way, the SC in Miller did not rule that "a sawed-off shotgun had no place in a militia".
The actual decision included:
"In the absence of any evidence tending to show that possession or use of a "shotgun having a barrel of less than eighteen inches in length" at this time has some reasonable relationship to the preservation or efficiency of a well regulated militia, we cannot say that the Second Amendment guarantees the right to keep and bear such an instrument. Certainly it is not within judicial notice that this weapon is any part of the ordinary military equipment, or that its use could contribute to the common defense."
It would have been easy enough to show that the US Military (including militias) had used short barreled shotguns since probably the Revolutionary War - most certainly by the Civil War, but no one offered such evidence to the SC in Miller.
No evidence supporting such had been presented to the SC (Miller and Lawton were not represented before the SC; only the US Government presented an argument - and they weren't about to offer evidence supporting Miller/Lawton), so the SC remanded the case back to the appeals court for consideration - which never happened since Miller was missing and Lawton was dead. (Hope I explained that well enough.)