Those of us who live on the coasts might discount St. Louis and the two Kansas Cities as fly-over country. However, both are relatively big cities. St. Louis has a large university, a regional medical complex that covers 7 or 8 square blocks, working mass transit, and a good deal of industry. Last month when I was there, helicopters never stopped flying in and out of the hospital heliport.
Kansas City is two cities straddling a river and state border: Kansas City Kansas, and Kansas City Missouri. It has more population than Atlanta or Miami.
The hyperloop has a lot of human issues people seem to underestimate. Current designs would be uncomfortable and claustrophobic, and safety of a big thing moving really fast in an evacuated tunnel is problematic. High speed rail, on the other hand, can go really fast without the problems. The assumption that a hyperloop would be less expensive than rail is unfounded and untested. And the hyperloop itself is little tested other than models on a short, linear track outside of SpaceX. The hyperloop may be real someday, but that time has not yet come.