I'm talking about the physics, not the logistics. Logistics are a present challenge, but physics are a hard limit, so load capacity and power conversion losses don't really have the same insurmountable bearing as rolling resistance and drag. Drag increases with the square of the speed, so fuel efficiency is really only comparable at a given speed.

Water is extremely viscous, so it creates a lot of drag, and cargo ships must scale to huge sizes and stay under 20 knots to have high efficiency. Trains are only flowing through air, which is much thinner than water, so freight trains and most passenger rail go double or triple that speed. High-speed rail doubles to triples the speed again, but is much, much less efficient than rail traveling at freight speeds, because it has no means of avoiding the added drag.

If you were to try and increase high-speed rail by another two to three times, you'd need a rarefied tunnel to make it approach being practical, which is basically what Hyperloop proposed. It's much more practical to use the already existing rarefied atmosphere at high altitudes, which is why airplanes have unmatched efficiency for travel at those speeds.

When travel time going into days or even weeks doesn't matter, e.g. for cargo, all that matters to efficiency is how slow you can go. When time is taken into consideration, as speeds go up rail becomes more efficient than boats, but they top out and airplanes are more efficient than rail. Eventually sub-orbital rockets become more efficient than airplanes, but there isn't a lot of travel needed at those speeds.