6. It is POSSIBLE (though probably really pushing it) to come to such a conclusion
It is not the most likely interpretation which is exactly which time frame of weapon is not at issue (I honestly don't see how such is even inferred any more than free press not applying to TV and radio) but establishment of the guarantee of a principle.
I also see an acceptance of a level of parity with even the military, if such was issue division would already be set.
At the time, folks might very well come to to serve with a better weapon than was ever going to be issued to them.
Hell, even very recently I know some cops bought their own semi-autos and only more recently got the option or were just issued semi-autos.
The debate if commoners should be allowed to be armed is ancient, the argument of scale to a soldier or policeman is pretty new and not really supported by reality until really the machine gun "ban" in response to gangs motivated by prohibition. A solution to a problem that otherwise wouldn't exist.