I think XB1 port would help tremendously. As far as psychical goes, maybe they can calculate how much it would cost for backers and only do those numbers?
It all depends on what Sony agreed to help support the Kickstarter, i'd guess.
If their support is worth more than the influx of income they might get from an XB1 port then obviously they won't/shouldn't do it, but otherwise they should.
I must say, I find myself a bit bemused at this idea of "support" Sony are giving the project. Not from a port perspective (I have a PS4, i'll just get that version) but only intending to release it in English/Japanese initially and have other languages (including those spoken in places like South America) as stretch goals seemed strange.
I understand Sony not wanting to throw money at it, but surely if they were to be providing support and giving the project the best chance at succeeding, then they could have been a big help for localisation especially with Playstation being such a global brand and particularly in Europe which would have opened it up to more people from the beginning.
Obviously they went through most of those languages for subtitles pretty quickly, but was always a strange one for me and also somewhat limiting.