I dunno, I sure as hell never asked for Unix. That was a decision made for me by AT&T and it's monopoly a decade before I was born.
As for why "the real, usable stuff" gets written in C? Because C is the only first class programming language in the operating system.
And of course 20 years ago "the real, usable stuff" was actually written in assembly because C was slow and inefficient. Or Fortran if you needed to do any math more complicated than middle school algebra.
Well, the "decision" was actually the consent decree in the AT&T antitrust case, which said that AT&T couldn't go into the software business. (Note well that AT&T did not have any kind of a monopoly on computer operating systems - not then, and not ever.)
The result, though, was that Unix became available for the cost of distribution plus porting, and it was portable. It was the easy path for a ready-for-real-work non-toy operating system on new hardware.
As for why "the real, usable stuff" gets written in C? Because C is the only first class programming language in the operating system.
And of course 20 years ago "the real, usable stuff" was actually written in assembly because C was slow and inefficient. Or Fortran if you needed to do any math more complicated than middle school algebra.