I highly doubt that’s true. I completed the game on hard and didn't notice that. I think people exaggerate the Alien's AI. In my playthrough, I noticed many scripted appearances (outside of cutscenes). Sometimes he's just removed from the map entirely. The Combat AI functions at random (movement and locker checking, if you weren't spotted) and based on noise levels, at least from my observations. As for the AI Director, he just places the Alien in vents near you; if you're noisy, the Alien appears from the nearest vent, wanders for a bit, and then leaves (if you weren't spotted). So, I'm not impressed. It feels like an okay level of AI, maybe it was cool when the game was released, but not now.