So what is the point with your example then? It doesn’t work like that.
The idea is that if games were less expensive then they would sell more copies, making up or exceeding the difference in revenue. Especially with digital distribution. The trick to earning more with a price increase is getting everyone on the sales curve to pay more, not just the people who buy at launch.
Considering new games will cost $70, for every 100 copies of a game Sony sells they earn $7,000 in revenue. If they sell the game for less than $70 then the idea is that more copies would sell during the same timeframe because more people could or would buy it. In their example they presuppose that at $50 for new games Sony would sell twice as many copies at release, so if the game sells 200 copies at $50 Sony would earn $10,000 during the same period, a 30% increase in revenue
Conceptually it works better for digital goods than physical goods because producing copies of digital goods these days is a small fraction of the cost of producing physical goods. Sony's network infrastructure is operating at a scale where it probably costs cents to create a license and serve a copy of a game where it's dollars for physical, which have to be printed, packed and shipped.
I don't think that Sony would sell twice as many copies of games at $50, but they would probably sell more copies than at $70. They would need to do 40% more in sales at $50 to earn the same amount of revenue at $50 that they would earn at $70. If they sold 50% more at $50 they would earn $7,500 in revenue for every 150 copies in the same period. The question is whether that's possible.
Another question here is whether going to $70 for new games will lead to a reduction in sales at full price. If fewer people buy at $70 than at $60 then at some point the price increase does not lead to an increase in overall revenue. AAA games at $70 will probably still sell enough because the demand for them is high. Demand won't be as high for every consumer because some will be turned off, but I bet Sony still makes more money at release than at $60.
It gets convoluted because at $50 AAA games would sell more earlier because people who wait for sales would buy earlier. Some people who buy at $40 may pay $50 to play sooner. But the long tail of the sales curve at a lower price would probably shorten. So again, the trick to earning more with a price increase is getting everyone down the curve to pay more, not just the people who buy at launch. How many people who wait for $40 will buy at $50? Or will more people now wait for a price reduction? I would say we have to wait and see. But since we don't get that info any more we'll just have to take their word for it.