I think Square Enix knows its audience for these HD cash grabs, they probably don't think the Xbox One is a worthwhile investment (yet) except for the bigger games like FFXV and KH3 and even then we'll have to see what the platform splits will look like which is going to be very interesting
Still, it begs the question on why FF Type-0 is multiplat and this isn't, also I can't imagine Sony paying for that FFVII PC -> PS4 port, they can't be that stupid right? Square Enix is a strange unpredictable company though so I guess you shouldn't always expect a logic answer for their decisions.
Bookmarked aww yeaah.