The bug

Iron Ore was changed to have "ambientocclusion":false, but it still inherits from block/cube_all. Gold Ore was changed to have no parent, but has ambientocclusion set to true. Coal Ore was changed to have no parent, but has ambientocclusion set to false. All models will obey the AO flag of their topmost parent. This does not seem intentional.

How the attached resource pack looks in-game:

The ore textures were modified to more clearly show the AO effects (and lack thereof).

Intended result: Iron Ore and Coal Ore should have no AO
Actual result: only Coal Ore has no AO

How to reproduce

An example resource pack can be found here and read the steps above.