I just got the Ormandy mono box from Amazon Spain. The price was right, but no-one else seemed to have it in stock. It came out less than six months ago. That one might be a special case, since some 4/5 of it was never issued on CD officially.
I suspect they're having trouble calibrating supply/demand. The Bruno Walter box (
https://www.amazon.com/Bruno-Walter-Complete-Album-Collection/dp/B07MWXGCWL) is a treasure, but a lot of people already had most of that box, which is why it's still available. I probably had about a quarter of it, but I was able to flip what I had and more or less cover the cost of the box. But of course most of what was in the Szell box was previously available too and it flew off the shelves.