This isn’t a guide, just something i think may help. To install Steam on an Arch-based distro in most of the cases a simple sudo pacman -S steam will do just fine.
The installation will ask you to select a valid vulkan package from a list. And in most of the cases that’s just fine… most of them.
Then you have your very “picky” old nvidia GPU which works only with a specific old nvidia driver and if you try to install anything else, there will be a conflict. Now you can try to remove the old (working) drivers and try your luck. But looking online i find a simple way to skip this passage and install Steam.
sudo pacman -S steam --assume-installed lib32-vulkan-driver
I suppose I’m lucky. Catchy installed the Nvidia driver during the install and works/ updates without issue. I’ve got an older card, but not ancient. gtx1660
I did have issues when I first switched to Linux, but that was on Debian.
Currently “older cards” is GTX 10xx series and earlier
This is a deliberate choice made by Nvidia with respect to their proprietary drivers, and has nothing to do with the operating system.
Cach6 was the smoothest experience for me. It can be difficult with other wldistros and also with cach6 probably.