From what I can tell (and I am not an expert): Zeronet and IPFS are really fixated with solving the P2P secure content distribution problem. They convolve the solution of that transport-level problem with what I believe to be the central problem, which is a distributed content integrity system. DAT is a technology is that primarily fixated on that latter component, and is relatively independent of transport.

I think that things like p2p transport via Tor, bt, etc. are all red herrings. The robust computing infrastructure for the next-gen, distributed information system that the world needs, should not be tied to transport layer concerns like that. It should work reasonably well via flash-drive-sneakernet as it does over fiber and LTE.