Also, it's hotfix #21 that seems to be causing the massive slowdown in graphics performance, not #20.
For me, Hotfix #20 made the game completely unplayable. Mainly, by introducing lots of frame stuttering.
You may not notice as much unless you're running at a high resolution (eg., 4k) at max quality (Ultra). Who knows. There absolutely has been a problem introduced though as many of us are having the exact same issue since hf21.
It might be an ARM only issue.
