I don't think people want to clone D3D11 (please note that D3D is not the same thing as DX). What people are saying is that OpenGL fits no more, and D3D11 is a nice example of how a good API should be.
As you say, OGL needs to be fixed. And actually, it's so urgent that it's almost already too late. Why? Because of GP-GPUs. OpenGL and most of Direct3D is tied to the current paradigm of polygon rasterization used in most (all?) games/apps out there. But rasterization has it's limits, and currently we waste tons of "brain cycles" figuring out tricks to go around these limitations and still improve graphics. Things like simple reflections on materials are pure "magic" tricks that you don't seem aware of.
We will not be building geometry mimicking real behaviour of atoms and so on for quiet some time (decades, probably...). The next step is realtime raytracing. GP-GPUs are bringing us closer and closer to being able to render very photorealistic frames faster and faster. You don't need very complicated tricks to render perfect reflections, depth of field and other realistic effects. OpenGL covers nothing here. OpenCL does. It's only a matter of time before OpenGL as it is dies. Meanwhile it has wasted people brain cycles that could be better invested in making actual functionality (gameplay for example) better.
Actually, the term GPU will probably die in your 5-15 years timespan as it merges with the common CPU (look at AMD and Intel with their new "GPUs" integrated on the CPUs).
From then on, people will no longer build software around a (less and less) limited pipeline like current GPU offerings have. People will create their own custom software pipelines that will give "unlimited" flexibility.
Coming back to today:
Today we are wasting brain cycles because OpenGL evolving too slowly.