It's not really that different though. Google is showing me a round trip flight between New York and Miami for $55. Amtrak wants more than four times that, and it's 27 hours each way instead of 3.

I feel like the premise of a train is that it costs less than a plane and uses less fuel per passenger, so it should be slower but have the countervailing advantage of being less expensive. That is not what I'm observing.