Every train seems to have a shorter consist.
The Empire Builder typically had 2 Seattle sleepers most of the year and always had 2 Seattle coaches. Now it is back to 1 Seattle sleeper after having a second over the summer, and never got its second Seattle coach after going back to daily. The Starlight was pretty close to a normal consist. The off season Starlight was usually a baggage, transdorm, two sleepers, diner, business class coach, Sightseer, two coaches. The peak season consists (summer and holidays) usually had a third sleeper and third coach.
There are a couple of theories that have been bandied about, but nobody really knows. Basically those theories are based either on Amtrak's management being merely incompetent or Amtrak management being hostile to long distance services, but unable to be as overt as they had been under Anderson due to the current attitude of Congress.
The OBS labor shortage I think most people acknowledge to be genuine and not entirely the fault of management, aside from letting the food service people go, because "Flex Dining" was going to be a big hit, and maintaining a crummy workplace culture that people may not have wanted to return to. People that were furloughed from Amtrak during the service cutbacks just got other jobs and aren't coming back. But the food service people weren't just furloughed back east, their positions were abolished.
Amtrak's incompetence: Equipment shortage due to not maintaining it or inspecting it during the triweekly period. Now they have a backlog of maintenance and just don't have the fleet to run full consists. The fleet was always just barely adequate to meet the schedules anyway, when routine inspections and maintenance were factored in, with little in the way of protection equipment.
Amtrak hostility to long distance services: While the maintenance backlog may well be real, Amtrak wants to depress ridership numbers so they can show justification for discontinuing long distance services when they get a more amenable Congress. The continued presence of Gardner, now COO, who has always been hostile to long distance services, is viewed as an indicator, despite Flynn's better PR skills than Anderson. Suspicion is they are executing a Ben Biaggini strategy of deliberating suppressing patronage to better support discontinuation of services they don't want to provide.
Personally, I believe it is a little of both. Amtrak's management has proven itself spectacularly incompetent in a number of areas, some not relating to railroad operations at all, such as their woeful IT operation. I do believe there remains quite a bit of hostility to long distance services in their C Suite and upper management levels, so they are not going out of their way to get the equipment back in service and get operations ramped up. Finally, there is the long standing attitude of Amtrak management generally where cost containment is the ultimate goal and they are largely blind to revenue enhancement opportunities and even blind to lost revenue as long as costs are cut. My own, very personal and not particularly well grounded, take is the current situation is maybe due to about 70% incompetence and 30% malevolence.