Most of it is relating to getting the stability benefits of Debian Stable while keeping your system modern like Sid (not necessarily just for gaming). Keep in mind that Sid is inherently volatile/unstable and a lot more prone to breakage, so I wouldn't recommend going that route unless you feel you have a real usecase, as you might find yourself needing to manually fix problems every so often on a Sid install. For a typical gaming workload I don't feel like Sid is required, and with just a couple tweaks (Flatpak Steam/Lutris + newer kernel version mainly) you can get Stable to perform the same role cleanly. You can always upgrade into Sid later if you feel like you really can't handle Stable's older native packages.

Also, idk if it was explicit enough but the point of the original post is that yes, Debian is great for gaming, even with Stable. I would base your distro decision on literally any factor besides gaming, because if Debian Stable can do it then every distro can do it. You mentioned annoyance with Red Hat in your original post, so a strong selling point of Debian is that it's a community distro. Arch Linux is also a great community distro that's bleeding edge like Debian Sid.

Debian is generally easy to use but it's still a tiny bit more DIY than most popular distros - if you find Debian too annoying to set up you can always try Linux Mint/Linux Mint Debian Edition, which is a very reputable Debian-based distro.