I do believe distribution matters somewhat. For example, Fedora requires a lot of messing around to get video playback to work. A non-techie is gonna have a hard time installing gstreamer non-free plugins and non-free ffmpeg from RPM Fusion (not to mention figuring out that that's what they have to do in the first place...).

Non-techie NVidia users will similarly have trouble installing NVidia drivers on distros which don't make that easy.

And some distros are less careful about breaking stuff on updates than others. I stopped using Ubuntu after too many updates where random stuff broke just because Debian Testing happened to have shipped a bad package at the repo sync cut-off in the Ubuntu release cycle. One update made the Nextcloud desktop client segfault on launch, another broke auto login in GDM and required switching to TTY and editing a config file from the command line to fix.

Whether the distro ships a software center which makes it easy to install snaps, flatpaks or both will also heavily influence how easy it is for a new user to install the software they need.

Yes, it's just different packaging of many of the same software components. But it matters a whole lot to new users who rely on things to just work without the skills or experience to customize and debug stuff.

Use Ubuntu/Kubuntu LTS , do not upgrade every 6 m0onths to get the latest bugs from upstream just because they GNOME/KDE made some small improvements for some feature you probably do not use. There are PPAs with latest kernels and NVIDIA driver if you really need to upgrade for your work or gaming. This shit on upgrade happens on cool distros too, just Google Arch broke on update and you will see that there were cases where the efi partition was deleted and the user data was lost or some font customization a dude done to GNOME broke the login after an update.

If you want to install Linux to a less tech person you install an LTS distro and enable only the security updates, you can install Firefox from upsteeam and it has auto update and install ad blockers on it but teach the user how to stop it for specific websites in the case the blocker breaks stuff.