Earlier quoted context omitted.
The US is ~263x larger than the Netherlands landmass wise. It would require a loooot more trains than we have or you have.
You put the trains where the people are, not in the middle of vast unpopulated stretches. Comparing land area is misleading and unhelpful.
The Netherlands, while technically highly urbanized, has remained more like a bunch of small towns instead of a few highly populated cities like as is seen in the US, so it is much closer to the rural days of yore when the US was able to support a comprehensive, nation-wide passenger rail system.