This has been true since the dawn of Enscape. The last advice I got was 1) lower the quality (really?) or raise the ambient (does nothing).
Thanks if anyone knows.
So. Interesting. It would never occur to me that the grass material texture would make a difference. But it does.
If you use a lighter green for the grass it may reduce the amount of green being reflected. Reduce the reflectivity of the white material under the deck will also help so that the material absorbs the color rather than reflect.
Note how the white quartz countertop (image below) reflects the brown (1) of the upper deck vs the white (2) of the sky? Enscape is reflecting reality.