So my question is lets say Dice are making BF5. Will they completely skip the use of soft body dynamics since GPGPU usage is so limited on the XB1? Or will they make a version of the game without it specifically for the XB1? Cause now the questions isn't a difference in resolution or frame rate. Physics are fundamental to the gameplay.
Edit: the point I'm trying to make is it appears to me that GPGPU usage is truly a next gen feature. But since one of the next gen consoles is lacking in that department if it will have a negative impact on multiplatform games.
I would imagine they'd use a different update rate, a 60 fps game doesn't necessarily have to have everything running at 60fps. Perhaps you would get 20fps destruction on PS4 and 10fps destruction on XB1.
Also as vcc says, it really depends on the install base and the software attach rate for third party games. They have to make money so they'll do whatever is best for them the things they'll need to consider when doing this are:
Competition - Both first party and third party support, IF BF5 can get GPGPU soft body dynamics working correctly it would give the yet another edge over CoD, this would be good for DICE. Especially if they are also competing against Halo and Killzone.
Parity - Parity is a word not used very well at the moment, the games need to have "Parity" between consoles but not exact parity, they need to have both versions running well, though discrepancies in resolution and frame rate dips are fine. This is only the case now though when sales are unconfirmed, if the XB1 somehow out sells PS4 comfortably then the last thing you want is a reputation for making poor XB1 games when all you actually did was make a good PS4 game, after a few years this may change.
Sales on each platform - If PS4 outsells XB1 4:1, the DICE won't care about XB1, PS4 will get full GPGPU systems and XB1 will get a reskinned BF4. If it is 2:1 with even atach rate then we'll likely get a GPGPU system across both, but if it is 2:1 and a lot of XB1 owners have a PS4 and are buying the better multiplat so sales on PS4 are higher than the suggested 2:1 from pure install base we may get more GPGPU and be closer to the full GPGPU vs. reskinned game. The Handheld/PS2 Fifa's are a good example of this reskin technique for low sales.
Cost - This is something Sony can help with, as we've already discussed the PS4 exclusive games are using GPGPU, If Sony were able to and would want to they could help by creating specific API's for GPGPU physics which would significantly reduce the cost i implementing them, I have no doubt Sony will be trying to do this to get an edge over the XB1, by providing something to developers that would be difficult to duplicate o the XB1 themselves and would likely require Microsoft to help create. If these are in place then perhaps we would get GPGPU on BF5, but only on PS4, MS updates the XB1 dev environment after this and BF6 is GPGPU on both platforms.
There are so many things to consider when implementing features like these on multiplatform games.
EDIT: the parity bit was rearding the difference between exact parity (we won't get that) and mainly parity (same game, higher res, higher framerate, better shadows)