Your assuming that aviation will ever have the lift capability that surface trucking has. As far as GPS guidance goes, it took a gazillion years (pardon my exageration) to certify WAAS and I think it will take a quintillion more to certify GPS, WAAS, and LAAS guidance.
True, government inertia can never be overestimated. I hope this talk of privatizing air traffic control could be an indicator that the regulatory climate is relaxing.
On the practical side, we use both ground and air transportation for parcels. Eliminating the cost of two pilots will change the ratio towards more air transport. Also Boeing is working on heavy lift capability (over sea.)
As impressive as the Pelican is, its carriage capacity pales in comparison to a Maersk ship, but its cost would give a herd of bean counters a heart attack. The cost of the overhead (crew) is miniscule compared to the efficiency, or lack there of, of the lift.