The reality is that Amtrak downgraded it's entire dining experience to save money. I assume they operate passenger service at a huge loss, and are striving to cut their losses. Step one: cut the least-used (or biggest loss) routes. Step two: cut staff. Step three: reduce the expense of carrying self-loading cargo.
Yes, the food is a shadow of its former self, but it's still fun eating while watching the countryside roll by outside large windows. And it's still better than typical airline chow. I will miss the experience I had on my first overnight trip on the Silver Star to NYP ten years ago, enjoying the steak, and having a server who, when I couldn't decide which dessert to have, said "No worries, I'll bring both." {sigh} The good old days are also both.