Me too. I've never understood it. I just went back through the clang-format documentation and looked at some of the examples for the GNU style and was reminded at how utterly unreadable the resulting code is.
I've not written a lot of lisp (I understand it, just never had a need for it personally) so perhaps I'm ignorant, but I don't see how it's at all similar to Lisp. It just looks different for the sake of being different.
I also dislike it for C (as much as I appreciate GNU's contribution). As we all know, K&R is the one true style.