Let me start by saying I think Linux Mint is one of the top 5 greatest distros of all time. It is an absolutely essential starting point for many people and their work is responsible for much of the user-friendliness you see in the world of Linux today. It is stable, has a nice aesthetic, “just works”, and doesn’t make you update constantly.
These things are great but they are the very things that make Linux Mint unsuited for online gaming. Is this a bad thing? No!! It’s just not a distro made for gaming purposes. It’s like showing up to a monster truck drag race in a Ferrari. I cannot count on my two hands how many times I have provided support to a user, to find their issue was outdated libraries due to using Linux Mint. It happens all the time. Go look at any game on ProtonDB that is currently working, and you’ll find 1-2 “not working” reports and they are always on either Debian on Mint.
I understand why we see it so often, because Linux Mint is awesome and users want to play their games on it. But if I suggested Hell Let Loose to a friend using Linux Mint right now, the first distro suggested for gaming in our FAQ, he wouldn’t be able to play because of his choice of distro. Making rolling distros look like a fortress in 2023 and suggesting Mint for gaming will only set new Linux users up for disappointment.
Realistically, people think of it for new user gaming because of the “just works” thing. Of course they also tend to recommend using the Steam flatpak, though it’s easy enough to screw up and install the native package instead and have issues. But there’s nothing wrong with suggesting a stable, “just works” distro as a base for gaming. You don’t want said base breaking after all.