It's simple really. Sony fanboys know that their 1st party exclusives really aren't that great (most are mediocre), and Sony will never dominate if they have to rely on them. The only way that any PlayStation console will be on top is by money-hatting their way to the top (PSX era), or by being the only game in town (PS2 era) and pretty much having all the games on their system by default.
Sony is back in the same position it was in the PSX days. They're going to win because of the screw-ups of their competitors, not the strength of their own product.
Common dude, most are mediocre? What about Uncharted 1,2,3, what about Killzone 2,3 that got some of the highest scores this gen, what about Journey, Infamous 1,2, Heavy Rain, The Last of Us, God of War 3 and LBP 1, 2. Every single game there is a system seller. To say Sony can't win by the strength of their own product, I mean common really? How many of Microsoft's exclusives for the Xbone are just third party games that they had to buy out? How many of the PS4 exclusives are actual first party games made by Sony studios? Sony has the best first party studios out of the big three, now for the best IPs obviously that goes to Nintendo, but the best studios goes to Sony. To say Sony can never dominate if they had to rely on their first party studios? What do you think happened this gen? When the PS3 came out at $600 and no one wanted anything to do with it, it was Sony's first party games that turned it around and it came back to sell more than the 360.