The idea that all weapons should be locked up when not in immediate use is not valid.
For most of history, weapons were never locked up. They were always available.
The idea they should be locked up is just part of the indoctrination to make us believe "guns are bad".
When I think of colonial America and our founders, one of the visuals that comes to mind is the musket over the mantle . It was accessible to any household member who could reach it. Modern efforts to push the locking away of firearms are intended to convince people that, "guns are bad," but any degree of critical thinking will lead to the conclusion that in general, people are no longer as disciplined and responsible as they once were.