I mean the article answers it, but this is not the first time that devs have complained that they MUST launch software that runs on the X and it's sibling, the S.
Like, it's a requirement that the game runs well on the flagship console and it's potato brother.
It's hardly a mystery why a dev might not want to spend time building a game that looks great on PS5, Series X, and PC and then also have to make a 2nd lobotomized version since Microsoft decided they wanted two consoles this time around.