The hardware developers (AMD/nVidia/Intel) have an interest in not changing their device drivers, the software vendors (OpenGL and DirectX) have little interest in redeveloping technology, and the software developers with the most capital, game engine developers, have already found workarounds and hire enough engineers to plug leaks in their lifeboats. The state of tools for game developers is so shoddy as well that trying to retrofit language compilers and shader compilers to work together seems like a drawn out task.
It's sort of a David and Goliath situation if you think you can change the graphics programming landscape on your own. Plus, we all know how poorly these standards are developed over time.