The problem is not the kernel. It's the anti-user hostility to open source (GPL3 utilities e.g. modern Bash and rsync etc) and open standards (e.g. OpenGL and Vulkan) that stem from an over-active legal department. And the GUI that's stuck in the past. The top menu hasn't made sense since screens got bigger than the original Macintosh. The Dock has always sucked. Window management is primitive and saddled with interminable animations. And then there are the random unconfigurable things like the stupid camera gesture recognition popup or the inability to use natural scrolling on touchpads without reversing the mouse wheel too. MacOS needs an overhaul.