These routes can be 70, 80 hours of runtime with only brief stops for a crew change
If something breaks it stays broken until the train can be serviced. I actually lack experience in clogging or unclogging Amtrak toilets so I don't know what must be done to keep them in service
Each superliner has multiple toilets in the lower level, most seats are upstairs but there are lower level seats particularly for folks who are not able to navigate stairs for whatever reason or just people who prefer the peace of not having people walk back and forth through the car (only the upper levels are connected by vestibule)
So anyway if you have a seat in the lower level you're down the hall from the toilets, and 2 or 3 days in the clogged toilets just stay clogged and it reaks
IDK how Amtrak does it, but on some European trains, crews will board a defective train for emergency repairs if necessary, and simply get off when done.
The zephyr crew really goes the extra mile with fresh flowers in the dining car, haven't seen that on any other route
Conspicuously absent from a visual diary is the odor of toilets out of service