It will probably not happen as long as there is a commercial incentive to not do that. What you will get is a subset of features that can be common in a shared

It will probably not happen as long as there is a commercial incentive to not do that. What you will get is a subset of features that can be common in a shared interface. At this time a GPU manufacturer will conform to whatever workloads will run on the device, instead of creating a shared API and letting someone else choose how to use it. Even if you just compare CUDA and OpenCL which makes use of the GPU in non-graphics workloads. In theory this was a chance to create a universal interface but in practise it turns out what you can make more money if your special sauce is better than the sauce of others, even if it's not better in all scenarios. It seems the true agnostic interface will be on engine level where a compute library or graphics engine will be running on top of a bunch of non-agnostic interfaces and the real interface you'll be working with is the interface of the engine.