[ivanjermakov]

Ambient occlusion is not only about realistic indirect lighting, but also about giving objects more depth. Great example here: https://developer.playcanvas.com/user-manual/graphics/lighti...

Also, looking just at inner corners of the room is too specific, SSAO affects creases everywhere, not just at the inner corners of the box.

[Maken]

These examples mention explicitely ambient light, which is the point of the article. SSAO makes no sense for direct ligth.