File management and some UI paradigms in general. Terminal.app isn't very comfortable. Package management feels hacky and various things seem to work better with various managers. And the need for 3rd party package manager for basic stuff itself. Absolutely terrible OpenGL drivers. The way library linking is implemented for the bundle files is horrible. Troubleshooting is hard. And those are just first things from a quick dump out of my head, I could type more.
macOS seems like a better, Unix-based Windows for me. Better than Windows, but that's pretty much the only thing I can say about it.