AO is derived from full GI with some extremely crude approximations. Anything that simulates full GI more accurately is implicitly a more physically accurate re

AO is derived from full GI with some extremely crude approximations. Anything that simulates full GI more accurately is implicitly a more physically accurate replacement of AO. Still, AO is not dead because it is still a rather simple and cheap cheat to add more visual definition to concave corners and highly shadowed areas. Sometimes, artists decide that their scene should have this extra touch.