Usually the original developer/publisher will target more than one platform - Windows, Xbox & Playstation are the usual suspects. Windows & Xbox use very similar (but entirely the same) versions of Direct3D, while Sony provide something roughly equivalent, normally closer to D3D than GL (the failure that was PSGL notwithstanding). That usually means the first thing a developer has to do is write a cross-platform wrapper API![]()
Game engines nowadays are cross-platform aware, so unless developers wanna build their own wheels, the barrier is lowered. Having said that, today's OpenGL is a hot mess. It is not about the feature set at all, but the disparity between implementations and the API design itself. So I would rather hope to see Metal for OS X instead (but Apple would have to make it work with Intel, AMD and Nvidia GPUs...), or one may hope OpenGL NG will come sooner than later... Let's wait and see if Apple will have any response in WWDC next year to DirectX 12 arriving late 2015.
O.T.: PS4 provides a DX11-equivalent wrapper GNMX, but the real canon is the low-level API GNM. Xbox currently provides a superset of DirectX 11 with some extra APIs granting low-level accesses, and will migrate to the low-level API coming with DirectX 12. By the way, IIRC PSGL is just something like GNMX, as a mean of fast porting to PS. Serious developers always go GCM.
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