But metaphors are great tools, if wisely used, to reuse mental patterns and find ways to use new tools. What would be the computer without the metaphors of the windows, buttons, files, and so on ?
Our brains also don't use files and folders, these metaphors having a direct analogy to our physical world in which we need to group things for easy access and distribution, however we are limited by the constraints of our world and the way we interact with it, constraints that will sooner or later vanish and pretty soon files and folders won't make much sense anymore.