Yes, before we get further along with this and complaints that are immaterial to my question, please be sure to read the fantasy scenario I presented.
My question is really about whether most Americans (or enough, at least) would be "comfortable" with doing an overnight train trip in a sleeper situation of some type.
And again, this question is about trips that can be done in one overnight trip, boarding in the evening/dinner (when the workday is over) and arriving in the morning/breakfast (before the next workday starts).
Any trip where you can do that, you could also board a plane in the evening and relax in a much nicer hotel.
This is simply a false statement. And that's an important thing to realize, Paulus.
The rise of the hub system on airlines has meant bizarre indirect routings with slow transfers; the major airports are an hour outside of town in Denver, Chicago, and New York... there are a number of places where you can go overnight by train, but your alternative is a 5-6 hour trip by multiple planes.
So you can board a plane in the evening and trudge into your nice hotel at midnight. Or board a plane just after lunch and make it to your nice hotel in the evening. Or sleep in your own bed, catch an early flight, and arrive at lunchtime.
.... or you can take the train. Many people, given those options, will choose to take the train.
Yes, this is due to a markedly inferior airline system to the one we had in the past; and a theoretical state-subsidized airline system with lots of direct flights (and no TSA) could steal most of the business back. That isn't what seems to be happening, though.