Sure. But that'll only happen if the Xbone isn't just outsold by the PS4, but actually bombs, hard (like, units left on store shelves everywhere). Remember, the added development costs will be very, very low. What's *most* different about this generation compared to previous ones is that developing for both consoles costs very little more than developing for one of them because they're more similar (architecturally, if not power-wise) than two consoles have ever been and because they're probably both easier to develop for than any consoles have ever been.
For the EXTREMELY MINIMAL added development costs of an Xbone version to outstrip the added money it'd bring in, the Xbox One would have to crater much harder than most folks are expecting it to.