This can't be taken seriously.

GuixSD in tier-3? It uses the same tech as NixOS - store-based hierarchy, and functional, transactional package manager. The only thing that's different is the language - Guile Scheme is functional, acts as a convenient way for REPL as well as debugging the system, and eliminates additional scripting dependencies, while also being great for meta-programming. One language to rule them all. And yes, uses Shepherd instead of systemd. Want more GNU in your GNU/Linux? Guix is the thing. You can also probably boot using Hurd, but I've not tried that out.

I will not complain about the rest of them because I've not used them well enough. But I know that this tier-list is just bad. ClearLinux has a really good package manager - perhaps, the fastest of them all. And the rest of them are well, based on a root distro, and good for their specific use-case. Debian and Arch is also used for testing alternative non-Linux kernels. Alpine offers musl C instead of libc and Busybox instead of GNU coreutils+/-binutils.