Cost cutting, pure and simple. Their financial situation is dire, so they are reducing expenditure in every way they possibly can. Covid gets the blame, even when that makes no sense. For example, on longhaul flights J pax get the same hot meal as those in Y. They could of course serve something a bit fancier in WBC (as far as I'm aware, most viruses do not have a preference for hitching rides on tastier food), but a penny saved . . .

Johan