Free and Open 4G radios/base stations are actually quite exciting for this reason. The thing which actually prevents mesh networks from working is mathematical: past a certain network size, path finding becomes too computationally expensive, so wifi based mesh networks can only cover a certain radius before they stop working. With the 4G spectrum, however, the distances between hops vastly increases, meaning that city-wide mesh networks can grow and remain performant. This allows for free communication and file transfer without centralized authorities. Obviously there are still threats, but there is a lot of freedom gained from network autonomy.