> The city is optimized to make travel distances as long as possible. No matter how you power those trains, shorter routes are more economical than longer routes.
Not true. What's more economical: a train straight up a very steep mountain or a train winding around the mountain? There are many situations where it's more economical to build an intentionally longer route to save money. Imagine a billion person where every single person can take a train directly to every other person. If you arranged every person evenly spaced in a grid you could connect them with less travel than if they were in a very very long line. But the train system would be much much simpler.
Not true. What's more economical: a train straight up a very steep mountain or a train winding around the mountain? There are many situations where it's more economical to build an intentionally longer route to save money. Imagine a billion person where every single person can take a train directly to every other person. If you arranged every person evenly spaced in a grid you could connect them with less travel than if they were in a very very long line. But the train system would be much much simpler.