I do believe they are looking for B/C capability, but not to give it for free. They may put it behind a paywall on PS+ special account, or PSNow. They may sell a DLC pack with "higher res" and other things. The fact that they make the console full BC may be just to be easier on them to do the ports and milking, not just to expend money because they may lose some customers. Looking at PS3 removal of BC, PS4 never having BC (and even digital classics of PS1 bought in PS3 doesn't work on your PS4) and X1 including BC and none of the 3 having any relevant impact I'm pretty sure Sony can get away without BC on PS5. At most what could happen is if PS5 get some hard time in the first year they will release free BC, before that they may invent any bullshit reason why they haven't made it available for free on launch.

If X1 which is weaker than PS4 can run X360 games that are on par with PS3 (some even performed better) then certainly if Sony wished to put the effort they would be able to do BC.

As explained by Pemalite in some threads. PC emulation of consoles need a lot of overhead and muscle because the creator of the emulator doesn't really need the internals of the HW. Sony knows it all. So if they wanted they could do BC of PS3 on PS4. The fact PS4 doesn't BC even PS1 show it have nothing to do with power. PS4 reads CD and DVD, they sell classic PS1 games and remastered PS2 games.

They wouldn't profit from free BC of PS1 and PS2 games (and considering data and PR probably most users wouldn't even use it much), but they got good revenue stream from selling these at cheap on PS Store with trophies, upped res or whatever.

X1 isn't Backwards compatible in the traditional sense. They are basically re-releasing the 360/Xbox games as digital versions. Plus you can actually buy majority of the 360/Xbox games on the X1 store as stand alone games where you don't need the disks to play them. Once you place the 360 disk in the machine, all it does is allow you access to download the game from the store, you don't play the games from the disks. This is why MS needs permission because they are basically re-selling older games and profiting from them. By law MS needs consent from the developers.

Well emulation is more CPU heavy so PS4's superior RAM and CPU doesn't quite matter there. Its already been discussed in this thread that the emulation of 360 games on X1 isn't done entirely by emulation. There are actually a few things being handled natively by the X1's APU, some baked in features likely intended for BC down the road. Basically that reduces some of the overhead of emulation alone (so less CPU power needed).

The PS3 actually had a more capable CPU than the 360 and many believe it would require more CPU power to emulate the cell versus 360's CPU. Whether or not that's true, there is evidence that X1 is not using just brute force power to emulate the 360.

Sony has made (or ported) a PS2 emulator to PS4. I own numerous emulated PS2 games on PS4. Not quite sure they would skip PS3 emulation if demand is so high, probably because they can't do it?

Eitherway, its likely PS5 will have the CPU power needed to emulate PS3. Which would be great even if they don't want to add BC per se, I would buy some emulated PS3 games with improved performance and resolution. Maybe even make other graphical improvements like Xbox One X does for some games.

The thing with the CELL is how relatively "stupid" the SPE's are... They are a dual-issue, in-order, lacks branch prediction and generally doesn't do multiple instructions per clock... They aren't an instruction/extension powerhouse either. - What this means is that they are an emulators wet dream. - The simpler a core is, the better it is to emulate and the less overhead you have.

The PPE is allot like what the Xbox 360's cores are built from... Which is actually the hardest part to emulate as there is significantly more going on... But because there is only one of those, it makes things a bit easier.

It's actually why the Playstation 3 emulator on PC is better than the Xbox 360 emulator, the Cell is simply a better CPU to emulate thanks to the design choices taken during it's initial design.

So whilst the Playstation 3 did in-fact have a superior CPU to the Xbox 360... For emulation efforts, it's actually irrelevant.

Perhaps you're right, the only thing we know so far is the PC emulator needs a lot of improvements before we can really start playing the most technically demanding games at full speed.

On a side note, I just noticed the Wii U and 360 are both using Tri Core PowerPC CPUs. Thus far is Cemu is the most efficient emulator running graphics at par of 7th gen. Still requires a good CPU to get a game like BotW running at a locked 30 fps though. If anything, it gives an idea of what CPU is needed for brute force emulation.

Yes and both of them will (play Xbox One and PS4 games)

Emulation is arguably getting easier in some aspects with modern systems like 7th gen consoles but by no means would I deem any of their hardware components to be "simple" including the Cell Broadband Engine ... 

The biggest reason why emulation with modern systems are getting more feasible is because much of the software we see from them isn't being built to the bare metal so instead of designing emulation around a low level approach such as simulating the registers, opcodes, or caches we can instead design emulation using a high level approach where we simulate the OS and it's system calls ... 

Believe it or not, quite a bit of modern software doesn't run directly on the hardware but they use kernels to interface with the hardware so in theory one could reimplement the kernel itself without having to worry about how the hardware itself would behave ... 

The only advantage PS3 emulation has over Xbox 360 emulation is because there is less complexity in emulating the RSX in the PS3 compared to Xenos on the Xbox 360 ... 

Yes you are mostly right. Sony can certainly make BC for PS1 to PS4 if they want. And they could have made PS1 to 3 on PS4 if they really wanted, that is the most relevant part of the discussion.

Well even if Sony doesn't want to make PS4 compatible with PS1 discs, at the very least they could port the PS1 emulator to PS4.

However, porting the emulator is the easy part. Seeking permission to bringing all those PS1 games over to PS4 is the hard part, maybe not worthwhile given many bought them on other platforms already. Hence, if you really want to play play PS1 games you could just get a PS3, PSP or Vita. However, it worth noting not every PS1 game available on PS3/PSP is also on Vita. That's likely a permission issue, go figure. Also people would likely get pissed if they couldn't access their previous purchases on PS4, so maybe Sony didn't want to bother.

Sony gave PS1 a break this gen, PS1 Classic aside. Maybe they will attempt to bring it back for PS5. They could already add it to PS Now if they desired given it has BC and many games in the store.

Neither XB2 or PS5 will be B/C for reasons I stated earlier. Way too much profit in re-selling them to us via streaming service or remaster. This trend will continue next gen with XB1/PS4 titles being remastered for the PS5. PS1-PS3 will be PS Now paywall. I'll see if Im proven wrong when the time comes. It won't be free either way like PS3 originally was with B/C.