PopOS gaming was a shit show for me, steam wouldn’t work and installing non free drivers borked my system like it was Ubuntu 12.04. I honestly don’t have any idea what PopOS does that others don’t for gaming, steam/wine/lutris/bottles are distribution agnostic. I’ve only ever heard people say PopOS for gaming but never seen anything showing why it’s better.
Full disclosure this was a while ago and I’ve gone separate ways with Debian and derivatives for now.
I’m onto fedora silverblue now since I like rpm-ostree. I’ve moved from laptop to desktop since then too, which could have colored my experience.