Although it'd likely sell as well to its fans without being a PS4 exclusive, and it'd get a 50%ish boost from selling on XB1. Whereas if Sony are publishing it, why is it coming on PC? Maybe PC sales were so low that Sony felt they could allow the devs to release on that without harming the benefits of their exclusivity deal.The SF2 games sold over 14 million & the SF4 games sold over 8 million. It might not be as big as it was but it's still a big deal & with the PS4 selling the way it has been selling without a real standout fighting game SFV could strike gold.
It's basically a matter of trying to determine whether this was Sony money-hatting the exclusive to secure it, or whether Capcom are choosing to ignore the XB1 for the time being. One's more inclined to think the former but it does seem a bit odd. The price must have been reasonably high unless it's a fairly short-lived timed exclusive.