The merits of different levels of exclusivity only matters to the individual pondering about it. Hypothetically, if I own a PS3 and a 360 but no gaming PC, it doesn't matter that the PC may have some of the same games as the consoles since I can't get them. What would matter is the exclusivity in the vacuum world between the 360 and PS3, since only that affects my decision making.
That's the difference between a gamer interested in what he'd like to own and a fanboy interested in winning some argument.