>Think of how short a distance "to orbit" is.
7.8 km/s delta-v, that's quite a lot.
>You're also mysteriously adding in build cost for starship, and not the train. Starship is reusable.
Even if both are reusable a train will last decades and a starship will be lucky to get a few dozen launches, which is still amazing mind you. Maybe it is my lack of imagination but i just can't see how a diesel engine that pulls a metal box at 60mph will cost more per trip than a rocket that has to accelerate to 18000 mph. Even just fueling: a train runs on diesel which is easy to handle and everywhere. Starship requires cryogenic fuel and oxidizer which is inherently more difficult to handle.