Interestingly, Brendan Eich called Android the Windows of the modern era just this week.
To me, ChromeOS has two things that make it far, far better than Android -- mandatory autoupdates and a far smaller attack surface. And, I think at a fundamental level those two reasons are why premium Android tablets just aren't appealing.
Maybe Android will be the default desktop OS, but in its current incarnation, it would be pushing a lot of brain damage on people.
ChromeOS != Chrome
It is just a Linux distribution with a window manager that only knows about Chrome.
"Internal politics" makes it sound like a mistake, but when Android replaces Windows as the default desktop OS in a few years, the Pixel C will look like a pretty smart idea.