I want to but don't know how or what commands to run to see what the issue exactly is. But I've tested on my 1650 and my Rx 5500. If you have 4GB of VRAM and try to game gnome does not like that. On KDE it will slow to a crawl but won't crash.
This is different. I'm talking about video memory. But yeah systemd oomd is shite. It works sometimes, when it does it takes a while of waiting before it does anything