zdnet[.]com/article/these-two-linux-desktops-are-the-simplest-picks-for-new-users/
Jack Wallen boils it down to the 3 versions that anyone can install & immediately start to use, with no learning, no skill, no figuring things out.
There is no science to this, as it's all about familiarity, stability, and usability. With those three things in mind, you absolutely cannot go wrong with KDE Neon, Kubuntu, or Linux Mint.