alt Hacker NewsI don't think the author makes a persuasive argument. Most of the photos they're analyzing are obviously lit by various point light sources, e.g.:
https://nothings.org/gamedev/ssao/IMG_0064.JPG
You can see a sharp shadow near the door frame. So yeah, ambient occlusion is not going to simulate that, but it was never supposed to?
It's supposed to make 3D shapes look good without the need to place lights or do more complex ray tracing. It roughly approximates what you could perhaps see inside a photographic lightbox. Light is coming from every direction and every surface is matte.
The reason it's used in computer games is not that it's photorealistic under all lighting conditions. It's that it makes geometries look better than before with less computational overhead than the alternatives. Harsh lights often look nasty and diffuse lighting is expensive.
one, the article is 14 years old. two, the point of ambient occlusion was not about making geometry look good, it was about making lighting look good.
The main issue it solved was normal lighting at odds with the world, it was for fast general approximation of global illumination.