Which makes Ubuntu basically Debian right? So just install that!
For a user coming from Windows I recommend Mint Cinnamon as it will give them the best, most familiar experience. Yes a newbie could find and install Ubuntu Cinnamon but the default ISO on the downloads page will saddle them with Gnome.
I hate it, basically I have to force myself when I boot into windows to physically disconnect the RJ45 from the back, so it doesn't replace the boot entries thru an update.
Big difference: Pop, at least, does not push Canonical's proprietary "Snap" nonsense. You can use it if you really want, but it's not installed by default. No snapd on my system, thanks.
For the end user, especially a beginner, there's 0 difference between them.
Shouldn't be the other way around? Beginners usually won't want to install DE's or other stuff by hand:
Linux Mint offers a Windows-like experience with cinnamon out of the box, and has several stuff setup by default like system snapshots and media codecs.
Pop!_OS is really appealing visually and very comfortable to use and setup.
I was scared to install Linux as a daily driver at first. Then Windows Update screwed up my install and I said "Screw it, I'm not installing Windows again". Basically Windows took the decision to uninstall it for me :)