The root cause is Americans, generally, prefer any mode of transit other than rail, so passenger rail isn't profitable, so train companies naturally prioritize freight.
For what it's worth, I like traveling by train and do so whenever I can, but I'm an outlier. Most Americans look at the travel times and laugh at the premise of choosing a train over a plane. And when I say they look at the travel times, I don't mean they actually bother to look up train routes. They just know that airplanes are several times faster. Delays suffered by trains never get factored into the decision because trains aren't taken seriously in the first place.
For what it's worth, I like traveling by train and do so whenever I can, but I'm an outlier. Most Americans look at the travel times and laugh at the premise of choosing a train over a plane. And when I say they look at the travel times, I don't mean they actually bother to look up train routes. They just know that airplanes are several times faster. Delays suffered by trains never get factored into the decision because trains aren't taken seriously in the first place.