It's not a failure. It's an option for developers who are constrained by the fundamental performance impact of a generic OpenGL layer when it sits between you a

It's not a failure. It's an option for developers who are constrained by the fundamental performance impact of a generic OpenGL layer when it sits between you and the hardware. The reason this is good is because it's platform specific, so it can make assumptions about hardware that Apple is in full control of. I'm sure the big engines will just support multiple code paths where needed. And any existing developer has the option to stick with GL.