TL;DR: A step-by-step installation of Linux Mint on real hardware and setting it up for typical gaming tasks.
I don't really care much for SOG's other content but his forays into Linux over Windows were incredible for demystifying the operating system to a mainstream audience (i.e. people who watch his content).
Some nitpicks:
- Muta should have used the flatpak version of Steam instead of the system package, the Steam client updates itself (with its own runtime and all) so using a system package over just sharing with flathub is a bit wasteful (it does complicate external storage devices a bit since you have to manually set permissions via flatseal but that's it). (Edit: this is just a small nitpick, the native system package is fine as well).
- There should also have been mention of Bottles over installing Wine as a system package as well as things like the Heroic Games Launcher for GOG and Epic Games titles, Lutris is fine though.
- On long term stable release systems like Linux Mint or Debian, Flathub (or foreign package managers like Nix/Guix) should be your go to for installing software, let the distribution itself manage its core system components which I wish he clarified when he saw Flathub taking multiple GBs on first download.
Other than that, Linux stays winning. 
Yeah it's mostly the Steam client being a proprietary piece of garbage since virtually all flathub apps have the correct permissions set (that's from my experience of using flathub for all my desktop apps since I use Fedora Kinoite). Same with Discord since there's now like 5 different webclients on Flathub just because Discord refuses to update their shitty electron app. I just don't want folks installing 32 bit libraries on their core system when flatpak is much cleaner (also better for getting support since its all one runtime). Same thing with Wine (which is on version 6 due to Mint being on 22.04's package base when current stable is version 9!)
KDE Plasma has permissions built-in to its settings so I'm hoping GNOME and Cinnamon follow suit.
my experience running it is mostly pop os and an arch variant on the pinephone so I'm probably not getting the best possible flatpak experience lol. I'm also not much of gamer so no recent experience with or opinions on steam...
My experience has been that most things will work fine but little annoyances will accumulate. I can't drag and drop files into Signal, have to use the popup file picker from inside of it, electron apps are almost always configured for X11 and require manual tweaking settings to get crisp text on wayland, some apps are literally useless without filesystem access and yet dont come with it by default and dont use the proper file picker that would let them load in files from outside their little jail.
better OS settings integration would help a lot
Libreoffice and Firefox are the biggest offenders (they both open the GTK file picker instead of the KDE file picker on Plasma). Very annoying but it's solvable.
yeah exactly like, these widely used, major apps have significant breakage that requires manual tweaking by the end user. It's frustrating and makes me very reticent to recommend flatpak across the board. If anything little apps that use flathub as their primary distribution channel are more likely to maintain their package well and use its features effectively lol, big orgs/companies don't put in the effort/take it seriously, or don't provide a flatpak at all resulting in unofficial ones which vary in quality.
Which sucks because I actually do like flatpak mostly. it's pretty much essential for my phone setup
I audibly gasped when I first found out how old most of the libraries are in the discord client. they were updated in canary for better wayland support like 6 months ago and I've heard nothing since. With steam dropping 32bit support hopefully those of us with native steam can offload those libraries soonTM
Don't know you case for Discord, but you should check out Webcord, it works like a charm with Wayland (yeah I'm 11 days late)