to an extent i dont think (hardware, which is what I took the OP to mean) sales matter, between the xbox/ps ecosystem. i can be told online xbox is selling crap and ps like sliced hotcakes ad infinitum, at the end of the day this cant be true because third parties (mainly the core third parties, activision, EA, Ubisoft, Take Two) dont drop support for Xbox.
of course, i guess ps does get some more minor exclusives on the japanese side ( i cant think of any, but more towards jrpg's and the like, besides SFV which is the relevant one I can think of). if those matter to you. they dont to me.
basically if your ps/xbox system, assuming you own only one of them, sells enough to maintain mostly full third party support, then in a sense no it doesnt matter to you, tangibly.
i left nintendo out of the discussion entirely, as it's a entire other discussion for them.