I think they would have sold a lot better, probably been their third straight 100 million seller. I can't imagine it making any difference on the games. Well, at least DVD vs BluRay. Who knows in regards to Cell.
But no Cell in PS3 would have made this gen more interesting. Does Sony still remaster so much stuff or is there PS3 BC eventually in PS4?
If the architecture could easily have been utilized by the PS4, I imagine you would have PS3 BC out of the gate Whether this means less remasters is debatable since a remaster would, theoretically, be better looking and more content complete. Like, I think TloU Remaster would still be a thing because it essentially acts as a 'GoTY edition'.
In fact, I imagine a similar thing will happen with PS5 (and XSX maybe?). There will be remasters but they will basically be the complete edition of the game, so FF15 with all content or KH3 with all content in a single package etc. While the content itself is not exclusive to next gen, that particular release will be.
Just my thoughts