Because, with the popularity of Linux, people have forgotten how varied unix-like OSes once were. I'm sure the grandparent poster will mention things like how i

Because, with the popularity of Linux, people have forgotten how varied unix-like OSes once were. I'm sure the grandparent poster will mention things like how it stores configuration differently, etc, but that's only not-unix-like to someone who hadn't used a handful of different commercial Unices back in the 1990s.