Non-interference, in a computer science or security context, typically means that the execution of one process doesn't affect the observable behavior of another. This is a strong property that's rarely perfectly achieved in complex systems.
Applying this to game AI: A "non-interfering" villager AI engine might imply that the actions of one villager AI unit have no effect on the internal state or behavior of other villager AI units, beyond indirect effects like resource depletion or pathfinding conflicts. However, some degree of interaction is practically inevitable. Villagers might compete for resources, follow each other, or react to events in their environment.
Therefore, while we can conceptually talk about *approximations* of non-interference in villager AI, it's highly unlikely that a practical implementation would truly exhibit complete non-interference. The design choices would heavily influence the level of interaction and apparent interference. So, the answer is generally no, a typical "villager engine" is not truly non-interfering.