The macOS Large Sur 11.2 kernel (XNU) supply has been launched right here: supply, tarball.
My earlier put up on constructing XNU for macOS 11.0.1 described the tactic for compiling open supply XNU for Intel Macs. This put up particulars compile XNU for each Intel and Apple Silicon Macs, and boot the customized kernel on each platforms. Word that it isn’t doable to construct or boot a customized XNU on Apple Silicon Macs earlier than macOS 11.2.
I doubt many individuals compile and run their very own XNU kernels, however the truth that you possibly can remains to be cool.