Shouldn't wide open areas make it even more suitable for trains?
No, and because of passenger density and volume issues that affects costs. For high speed rail to pay for itself, you need fairly dense-packed areas with high traffic between each other. For HSR to successfully operate on a large scale in the US, it's going to have to be a political decision to subsidize it and eat the costs (see: the Acela).
Even liberal-ish groups that Rah-Rah things like public rail admit that it simply isn't self-supporting in the US. A decade ago, Brookings did a study on American rail, and concluded that if AmTrak was to be "saved", it was going to require a mix of killing off some routes, and subsidizing the remainder:
What Brookings found is not surprising. There are only two routes that do better than break even — New York – DC and New York – Boston — and even those only make money on an operating basis, they don’t cover their capital costs.
Brookings finds that the operating profits (if the federal government subsidizes capital expenses) would cover the top 26 Amtrak routes (which carry 80% of passengers). They recommend having affected states cover the losses of other routes if they want those to survive.
I’m not sure how it would no longer be a subsidy if the states are paying rather than the federal government, but the supposition is billion dollar operating subsidies may no longer be in the cards for Amtrak. So how can they save the service that people actually use, while recognizing that the Chicago – California routes (Chicago Zephyr and Southwest Chief) are unaffordable. Fifteen routes account for over $600 million in annual operating losses.
Put a different way, Amtrak’s long haul operation is bleeding the entire system of the funds it needs to maintain shorter and medium-length routes where the passengers are.
HSR tickets are also naturally going to be more expensive than snail-rail fares, too, further hurting traffic numbers, especially over the longer distance routes.