first of all, considering any technology's efficiency in a vacuum is nonsense, so jot that down. If trains are efficient because the infrastructure already exists, then they are efficient, full stop.

second, that's not an opinion, it's just wrong. Trains are a way to move a maximum of weight along a predetermined route continually for a minimum operating cost. Maybe their only competitor is pipelines, and that only works for fluids. In every complex system the easiest way to reduce overhead is by bundling operations. Shipping everything in North America by long haul truck would require less coordination, but it would also cost more labor power, take more time, and destroy the environment more.

This idiot isn't actually a PhD, is he?

Physicist

Ah. So literally just some guy that paid for twitter.

Hyperloop

Scratch that, he's a guy that's trying to build a train but worse, and he probably got an email telling him he has to pay for twitter.

e: Also he has a fake company trying to bilk investors with a magic bullet perpetual energy machine. The dickriding is spectacular