Yeah... but if the packagers dont test it, or ship "stable" KDE Plasma 5.27 which will simply not get most bugfixes (Debian, MX Linux and many more will have these issues for 4 years!) its actually important what Distro you choose.

It is not if

• your Desktop relies on Xorg garbage which is "stable" and will not evolve
• your Desktop is minimal and Distros orient their schedule on it (GNOME)

This doesnt apply to

• KDE
• Cosmic
• Hyprland, Sway, Wayfire
• LXQt getting Wayland support probably

cinnamon eh?

That is actually very true honestly but also needing sonething as stable as Debian, bleeding edge as Arch or right in the middle with Fedora and also which kernel the user made need for their hardware is also a factor in this as well. DEs take priority tho as it's literally the interface you interact with 90% of the time

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.

I understand the argument being made, but I kind of disagree. Yes, picking a DE in which you'll be comfortable is really important (and often an undervalued aspect of using Linux for the first time), but I think that the time you need to spend self-maintaining your distro is more important, and is also prone to make-or-break your first-time Linux experience. That's the most important factor on whether a new user says "I love Linux and want to continue using it" or "I fricking hate Linux, it's filled with a bunch of problems, I'd rather just use Windows instead". And that's why it's important to recommend beginner-friendly distros, as to avoid frustration of newcomers, because those are more manageable (unless those newcomers want the frustration of managing something that they don't quite understand :)

Does it matter which one in specific? No, and it's probably at this point that the DE and visual looks should kick in.