“What do the scientific studies suggest that gun safes do?”
Every study I’ve seen shows a a gun that is unloaded and locked up out of reach is worthless except for planning a hunting trip some time in the future.
And that’s why attachable magazine fed pistols, rifles and shotguns are the best for home defense. I’ve even devised a system for single shot shotguns which allows a parent to keep ammunition in a ‘sleeve’ which quickly slaps onto the buttstock and allows for rapid reloading but can be kept separate from the weapon when not in use. I made several in .410 gage and sold them all at one gunshow. It was a hit for women to use as home defense when they have prying little hands still in the home.