Since you have already read the last post, I want to to get sure you get notified by this post here. I could find a way to compute nanite for a 8k landscape.
Hopefully this is a workaround for you, too.
I edited some values in the registry. Basically I did this here: GPU drivers crash with long computations (TDR crash) | Substance 3D Painter (adobe.com)
As thought, it’s a gpu problem - it simply timed out.