Running a train that's more than a basic day service (notice that Cal Amtrak doesn't run anything but buses overnight) is more of a personal service business than just transportation. The transportation is secondary to the experience. So you need more than just the basic train crew to run the thing. It's a hotel or resort, at least in part. Doesn't have to be a fancy one, though "first class" should provide some benefits for those those willing to pay for it. The railroads understood that, and the fancier trains (usually overnight at least once on the trip) were well-staffed to cover it.

Amtrak is (in its current incarnation - management has flipped all over during its time) mostly into basic transportation and pay for everything in the snack car (much like the cut-rate airlines), with "first class" getting showers, American Plan (meals included) and, sometimes, a separate lounge car not accessible to the hoi polloi. With the Desert Wind being seen as something that had to be run for political reasons, there was no incentive to make it nice. And being part of the City of Everywhere didn't make it a very timely train; no matter how you do it, splitting and combining trains takes time.