In console development, there is no such thing as "last minute update".
They will design console on certain cost and let some flexibility exist to have some leeway and alternative on sales tactic. Like with PS4 when they canceled PS4 camera to be included with PS4 and make PS4 more cheaper then Xbox One in 2013.
Ironically, The XBox One was considerably cheaper than the PS4 at launch. People seem to be puzzled by the fact that Kinect2 probably was a $250 "Add-on" at launch (it is and was expensive hardware), and considered the X1 to be more expensive. The $100 price difference not even marginally made up for the Kinect2.
Sales prices of consoles cannot really be reasoned as we do not know how recouping r&d and the other 10'019 pre-launch things are factured into the calculation over what time frame/sales numbers are accounted for. Ideally in the end, sales of hardware should not have been a significant burden on software sales. Each company's idea about that may vary largely, but the common idea "See that games pay for the hardware" is never correct.