I'm a little annoyed with the constant "Sleepers costs $1000s of dollars, we deserve gourmet food!" First of all, most sleeper fares aren't usually "$1,000s of dollars." In any event, the cost saving from the flex meals isn't the food (food is cheap, too cheap, in this country, that's why obesity is such a major health problem.) The cost savings comes from eliminating the labor costs in food preparation and the labor costs in the table service. That's why I think that Amtrak management can provide better quality flex meals, but I understand, especially during the pandemic, why table service needs to be suspended. If you think Amtrak sleeper fares are expensive, I would suggest looking at the prices for the private-car excursions or rail cruises that tout fresh-cooked gourmet food. Those will cost much, much more than an equivalent Amtrak trip. (I checked out the Rocky Mountaineer -- a 2 night jaunt from Vancouver to Banff is priced at $1,700 pp Silver Leaf, $2,400 -- Gold Leaf. And that only includes 2 breakfasts and 2 lunches. You're on your own for dinner. It does include the hotel rooms in Kaloomps and Banff, though.
By the way, my flight from Dulles to Beijing cost in excess of $2,000, and you wouldn't believe the lousy food we had. I could have upgraded to business class for another $1,500 each way, and then I might have gotten somewhat better food, plus a lie-flat seat. (Yeah, I know you can find cheaper IAD-PEK coach fares, but our bosses really do want us to be able to cancel trips without penalty, check bags for free, etc.)