Said this in the other thread, but think of it this way: No one can find an Xbox right now. Not even the Series S is readily available. Why waste the perfect PR opportunity at this time?
Stock is non-existent. They're either going to wait for each Bethesda game's big show, where they can REALLY put some excitement and momentum behind the exclusivity announcement, or will wait for E3/Summer altogether. It never made sense to do it now, Xbox never said they WOULD do it now, and there are no logical reasons TO do it now except to quell the fears of nervous Playstation diehards who will do whatever it takes to not buy an Xbox.
Spoiler: If you like Bethesda games, buy an Xbox/PC :)