I had tried to specify KWIN_DRM_DEVICES=”/dev/dri/by-path/pci-0000:01:00.0-card” and for whatever reason KDE didn’t want to boot into wayland anymore, but on the login screen I switched to x11 and instead of only engaging a few of my DisplayPort monitors – all of them were engaged. They were all forcibly set to 30-bit, but none of them demonstrated the types of visual corruption or blackouts I observed.
I found that having the steam store page on the home screen open would cause a particular monitor to drop out increasingly often, while causing corruption on other monitors in the same chain.
Everything about my config is the same as stated above.