Rail

The railway was originally invented as the most efficient way to move a heavy load across any terrain.  As well as the use of a smooth rail, reducing rolling resistance by two thirds, coupling allows capacity (or occupancy) to be extended.  A single engine and driver can replace one per carriage.  A safe interval at speed is needed only between trains, maximizing flow along the track.

A single train replacing many trucks

Scheduling a continuous unimpeded path to every service is the third great trick of the railway, gaining both speed and predictability.

Trains can be long, rather than wide.  A conduit can be less than half the width of a comparable road, with around forty times the capacity per unit aperture, and three times the speed.  A railway can thus offer (at least) twenty times the value for money.

Last, but perhaps most important, a railway can easily be electrified, and can now be fully automated.

From now on, boys will have to dream of something other than driving trains.