@GarGx1: Rumors are saying $499. So they would take a small loss but not much. That's common for console makers in the first year.
That wouldnt be a small loss if you factor Harddrive/bluray/power supply/ casing/motherboard. Its highly likely it will have an upper midrange GPU but the Cpu is quite likely it will be a lower end part . I dont believe they will do the mistake of using an outdated CPU design like the one on PS4 but i doubt it will be anything more than a lower end ryzen 3 ( which still would be a decent choice )
If that's the case, I don't expect Sony to include PS4 BC if they want to keep the cost down as much as they can. PS3 price at the time was high due to PS2/PS1 BC making it more expensive then the Blu-Ray drive did.
And let's take into consideration that Sony most likely will take some of the ideas from Nintendo's Switch cause as it is, the sales are down in Japan. It's hard to say what Sony will go for.
PS4 BC will be easy as its x86 based and not having to be emulated as with previous consoles.
Sony's PS4 BC issues are time sensitive resource sync issues e.g. a simple PS4 BC with PS4 Pro titles needs to have correct clock cycle timings. PS4 is NOT a PC when it comes to resource management. Sony has more than 5 years to figure out BC virtual machine for non-symmetric scaled hardware upgrade.
Typical console programming wasn't designed with PC's clock speed scaling such as boost mode or power saving modes.
MS has fancy virtual machine (VM) XBO on X1X which can fake XBO and XBO S behaviors. DirectX on XBO has less of sync resource timing issues since XBO titles can be boosted with X1X's extra power without major problems. DirectX's resource management deals with resource sync issues which give MS higher liberty with hardware upgrades.
X1X dev kit has extra retail X1X VM mode since X1X dev kit has full 44 CU enabled GPU.
Both Vulkan and DirectX 12 APIs has to deal with PC's clock speed and timing differences.