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 made this change like back in December or so. I had been distro hopping since moving to Linux in August of last year and was on a ton of distros with KDE that all had Wayland.
I moved to Mint Cinnamon because it seemed to be one of the few that wasn’t using Wayland and my issues stopped. I believe they did have experimental Wayland on one of the versions and I made sure not to use that one since I was under the impression it was due to Wayland and remember trying to decide between the other options they had.