To prefix, I would like to mention that this was already reported. However, the original poster falsely marked a post as a solution when that was not the case – it was not fixed or even alleviated, and as such, for posterity, I am making another thread on it.
As per the original post, you can see a huge difference between ShadowMap and Future lighting modes.
ShadowMap
Future
The lack of ambient occlusion in Future lighting is incredibly jarring, and makes our maps look flat and uncanny. We are unable to switch between lighting technologies at runtime, and as such we cannot switch between Future and ShadowMap based on indoor environments – where Future shines best – and outdoor environments, where ShadowMap vastly outperforms Future in visual fidelity.
Expected behavior
I would expect the same levels of ambient occlusion to be applied in Future lighting, as there is in ShadowMap lighting.
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