The US Supreme Court case, Miller, agrees. However, the Miller case has been misconstrued by every court that took it up, including the Heller court. Another case that has NEVER, not one time, been cited for what it says, rather has been cited for the opposite of what it says, is Presser.
I think you have far more knowledge of SC and precedent issues than I. But to a truly lay person, I think these decisions are really messed up too.
When the BOR was written the word "regulated" was taken to mean "trained" so that as Jefferson said and I paraphrase, the nation be trained up in the use of arms.
Fire arms handling and training in their use should be part of the public school curriculum at least from grades 4-12.
When people are familiar with tools they no longer can be fooled into fearing them.