OxygenOS 14 videos slow down screen when playing videos

Updated my OnePlus 9 Pro 5G to OxygenOS 14.0 and it seems that playing videos of a given frame rate will reduce the frame rate of everything else on-screen to that frame rate. I understand why this feature might exist, but I don't know how to turn this feature off.

First and second attached images show Cookie Clicker as an example: Cookie Clicker can play at 120 fps (though it doesn't have the frame time of 1 second / 120 frames ≈ 8.3 ms), but having a 30 fps YouTube video in Picture-In-Picture will reduce Cookie Clicker and the Game Engine UI's fps to 30. Third attached image shows what's available in my settings for video, mainly "Video motion enhancement", which doesn't affect anything.