edit: Fedora it is then!
He will be running the AMD 9800 X3D w/ RX 9070 XT, B850 motherboard.
I am deciding between either Fedora (probably KDE) and Bazzite (also KDE), but I’m not sure whether an atomic distro would be better/worse for a newbie.
As far as I understand, atomic distros can be easily rolled back after an update, but you are unable to use apt/dnf/etx, you need to use Flatpak, I think. Would that be limiting for the average user? Also, does Bazzite have better driver support for newer AMD hardware compared to Fedora?
I heard that Linux Mint doesn’t play nice with newer hardware? Or is that only an Nvidia thing
Anything Ubuntu-based (and thus Debian-based) may not be the best choice for brand new hardware, as it takes a bit longer for all the drivers to make it into the kernel.
It has to do with LTS kernel (iirc) making it incompatible with certain new(er) hardware. I recommend Fedora KDE.
Mint is based on Ubuntu, which has a Hardware Enablement Stack offering newer kernels. I would expect that (or maybe something Mint-specific) to take care of it.
I still would never recommend a “stable release” or LTS distro because the vast majority of security vulnerabilities never receive a CVE, and as a result the a large amount of vulnerabilities go unpatched for months. Also I like distros that take security seriously (Fedora and openSUSE).
Usually they backport security fixes to the stable version.
As I mentioned, most security vulnerabilities are not reported because it may not seem security related. The distro maintainers can’t keep up with every package and read all the commits, so as a result security fixes often go unfocused. It is a real big problem that many security researchers acknowledged.
I ran an older Nvidia card an currently a new amd card on Linux mint without problems. I suggest you try it out first using a live install on a USB stick.
It also doesn’t have HDR if that’s important to you. I switch into kubuntu whenever I want to watch something in HDR.