Preposterously, that paying her $55K/year (plus inflation plus her keeping her own salary) isn’t more than what Shulchan Aruch specifies as the amount of mezonos for one person.
When I asked about the times he doesn’t even have a chiyuv to pay her any mezonos at all (yet the prenup makes him pay), they didn’t give me an answer. (Offhand, one of them might have said “but he agreed to it”; all that means is he agreed to pay a kenas.)