When all you have is a hammer, everything starts to look like a nail.
Windows runs OpenGL just fine (look at anything iD Software puts out). It doesn't run Google's custom Java VM, it doesn't offer AOSP APIs and it doesn't offer Google Play Services. THOSE are the obstacles to running Android apps on Windows, not your obsession with OpenGL vs DirectX.
Is there OpenGL on their mobile platforms? It can run just fine in theory there, but it's not available. Applications are not limited to Java, and often rely on the graphics system a lot and there can be as well native code.
Windows runs OpenGL just fine (look at anything iD Software puts out). It doesn't run Google's custom Java VM, it doesn't offer AOSP APIs and it doesn't offer Google Play Services. THOSE are the obstacles to running Android apps on Windows, not your obsession with OpenGL vs DirectX.