no, there will always be a demand for a physical form of any currency that can be easily traded off without hassle, fees, and other procedures that might hinder the process of a simple trade. why go through the process of sending a transaction, paying a fee, and waiting for confirmation times for a small, everyday transaction? it's just incredibly inefficient. what im reading about the lightning network is supposed to rectify this issue, but im not too sure yet, ive still got reading and catching up on the subject to do. physical forms of currency provide a practical, simple solution as well as an alternative form of payment that doesn't require a network connection for people (i would imagine the connectivity might be an issue for some people in various parts of the world).