Agreed, because for most practical purposes there are only two valid distros in the first place (apt-based and pacman-based)

Sudo alone should be the deciding factor.

Meh, I feel that the only important choice is the type of distro; source, rolling, stable, immutable, reproducible, etc. as that'd impact difficulty to some degree.
Beyond that, it's not a big deal. Newbies will just pick the DE their most comfortable with. The popular DEs don't really have difficulties, just differences.

not really, compare installing something like Spotify on Ubuntu vs something Arch Based, something that allows you to access AUR packages with a few simple clicks.

For short-term comfort yes, though eventually the hassle of switching may outweigh that, and some users may prefer a longer-term view?

Linux users fall into three categories. People who want stability over everything else, people who want everything to be bleeding edge, and people who don't use desktop environments.

The most important thing for a new user is understand which of those three they are.