Shadows will still cast no matter where the sun is and the one with missing shadows significantly degrades from the scene lighting. It destroys the realism.
AO is also independent of Sun direction. It's the accumulation of bounced light all around the scene. There should naturally be MORE occlusion shadows all over the place. Objects near other objects need to cast shadows on each other. Period. Having RT AO will capture even the small objects like cans on the ground which the screenspace techniques can NOT capture.
Here is what you guys can't seem to identify flaws and rendering errors and that's because you aren't used to seeing what's actually correct.
There is WAY too much light in areas that should be occluded and not enough light in areas that are in complete shadow. The bushes on the ground have no self-shadowing like in Cyberpunk so they look flat -- just like RT OFF sceenshot in Cyberpunk (see how tech is at a standstill from UC3 to Cyberpunk RT OFF??). They painted in the root of the bush black to the tip of the bush but that's not convincing at all -- there's that artistic talent at it's limits there. You can't fix it. It's completely absent the technology to light that bush with a real light source taking into account shadowing. The light illumination on the stone pillar on the ground is too high. Again, no shadowing to tone down that brightness. In the upper floors where you can see inside, it's completely dark but light doesn't work that way. You should see more of the inside since the building is broken and light spills in a little bit. The underpass has too much light and the walls should be providing shadows on each other.
There is NOT enough light in this cave where RT GI will solve this. The light from the outside doesn't bounce at all inside this cave accurately and so it destroys the illumination from behind him as well as on all the walls that face away from the light. This is because it's using a simple light equation that says if my object isn't facing the light, then don't illuminate me at all. There is NO tech present where light would bounce around on walls that it does hit and come back to the objects that aren't receiving direct light and the back of Nate, the ground areas, and the dark patches of the wall
would be illuminated.