The author tries to explain this by portraying installing a new desktop environment as impractical:
> First, I tried KDE Plasma but was quickly reminded why I didn't much care for that desktop environment (it's too much like Windows). Then I tried Enlightenment, but that environment didn't much care for Wayland, so it was a no-go. I was going to install standard GNOME, but that would break Pop!_OS. Pantheon? Nope.
But it seems unconvincing. Universal Blue is neither going to fix the author's distaste for KDE, nor that Enlightenment doesn't support Wayland. And the fact that GNOME and Pantheon cannot be installed on Pop!_OS doesn't mean we need yet another whole new distro - just choose an existing distro that _can_ install new desktop environments! I know Arch can, and probably its derivatives and many other popular distros too.