Only aplies to proprietary stuff. Linux doesn't work that way. Appearantly it works, so why change it? Also: Linux has kernel modules.A good kernel design and api that allows modularity and all kinds of stuff is key to a good operating system.
Linux has an API?As an electronics student, I have seen way to many people who just don't get that you need api's here too. For developing drivers you need a kernel api.
Here's your graphics API -> http://en.wikipedia.org/wiki/Direct_Rendering_ManagerOpenGL needs graphics cards, that need stable, advanced and mature kernel api's to make their drivers work reliably and efficient.
What do you mean? There are tons of API's available for Linux... And stable at it.An operating system allows the programmer to use the same api for millions of system configurations and electronic parts. The same thing is true from the perspective of that hardware. To make it's api's available for millions of programs.
Also... As long as the kernel hackers and distro's solve the problems, the programmer can focus on stable APIs for programming apps, like OpenGL or whatever....