I think Sony is doing the smart thing. What's better?
-Continuing to make/market an old system heavily, knowing people aren't buying games there as much as the current gen.
-Focus on the current gen device, make few old systems and spend little on marketing it (if any).
I think the Big 3 have found out that there is far more money to be made pushing current gen devices. You get more water squeezing a fully submerged towel than you do squeezing one that was wet a few days ago. What they care about is pushing their "wettest" console, I doubt they care much about lifetime sales since old gen consoles aren't selling nearly as much software as they used to.