“They aren’t a bearable arm. They are merely an accessory and should be treated as such”
I hear what you are saying but the logic could also be since they are not a firearm then they can be prohibited.
In that vain, so could pistol grips. They are not firearms, just an accessory. So are scopes, and slings. Just accessories.
Arms, IMHO, include all accessories and ammunition. Yes, the above items are accessories but they are comprised under the word “arms”.
I see what you are saying.