I think I already have similar troubles with that about Radeon gpu. Their driver (or window11 itself) directs all GPU resource into the foreground app aggressively and basically stop the background app from using it. But I am trying to recording the game using obs. This basically make obs unusable if the gpu is near 100% usage. And sometimes it went even wrong, It decides to direct all gpu resource to the browser on my second screen, and I got 30fps on the game. I usually need a reboot to make it work correctly again.
I'd like them just add a toggle to let me select who use the gpu first or evenly instead. And their guesses never went right.