Well if the cut makes the total profit lower there is no point in doing it.
I firmly believe the PS4 cost sony around $200 to make right now. +/- $30.
If they lave the price at $299 sales will be sinificantly lower next year than it was this year. That seems ok if they can still sell like 14M consles at around $299 but at some point that starts becoming counterproductive. At some point the $60 or so that they make on the hardware frm the reduced number of consoles sold each month isnt worth it when You can sell at a lower price, selling more consoles and more software to the new buyers.