any chance you have some video pipeline insights?
So the biggest bottleneck is going to be the compositor. If it’s compositing a larger frequently changing surface (like a video on one screen and a game on another) yes you can potentially hit bandwidth limitations.
The right solution here is to use direct scan out to bypass the compositor. For example Kwin will do this when applications are full screened.
You want both the video stream doing this as well as the game doing this.