Really? This is the site for amendments (for now at least). It’s the second result when I search. Second to Wikipedia.

I can see the argument for what you said, but it pretty clearly isn’t the primary reason, looking back with a historical lense. It also specifically says “well regulated militia” which definitely does not refer to people with no training who never use their weapon having one in their house. Usually a militia would store their weapons in a central place and would also train to be ready when called. The individual storage and ownership thing is not the expectation historically.