Originally posted by Armos:

Simply turning shadows to medium helped a ton for me. Lagged quite a bit on high.

I dropped them to low and it literally doubled my fps in heavily shadowed areas like forests.

The other day I realised I'd actually forgotten the shadows were on low; the game looks that great to me with that one setting turned all the way down.

I always run the game with Vulkan, as it gives me massively better performance.
I'm aware this setting can have a wide range of effects, from crashes (which I literally never get) and lower fps to smoother performance like I got, though.