[hexedpackets]

Absorption is directly correlated with frequency, yes. Their 2km mile is probably a lab condition free-space number which will never even come close to being reached in the real world, especially in urban areas.

This could be useful to a telecom if they implement an expensive design that uses obstructions to their advantage. Essentially blast the radio waves down streets as if they are isolated tunnels. That would reduce interference to almost nothing, but require many more access points than they currently have. They would also still have the problem of penetration indoors.