I think the main complaint would be that it means Linux users will create bugs and security holes if they aren't constantly keeping track of the fact that a hug

I think the main complaint would be that it means Linux users will create bugs and security holes if they aren't constantly keeping track of the fact that a huge chunk of the computing world doesn't follow the same convention. To me it smacks of a rather egregious failure to grasp Postel's law. And case-sensitivity is just bad UX for the 99% of computer users who aren't programmers or IT; perhaps it makes sense on Linux but Windows and OS X are dealing with a different audience and Linus's failure to give that fact some credit makes him come across as tone deaf.