Yes, changing distros to change DEs is simply nonsensical behavior. If one's distro doesn't support multiple DEs then it's probably time to reconsider if taking reddit's advice on the ArchLinux-spin of the quarter is actually a good idea.
Not sure what the point is, but "creating your own OS" by forking Debian / Ubuntu / Fedora / Arch and changing the wallpaper (only slightly hyperbolic) still seems to be somewhat popular. One of the best outcomes was RebeccaBlackOS, which ended up being an early testbed for Wayland on the desktop.
