He was the director of AI at the company, an important position. Notably, however, the AI director position is distinct from the director of the Autopilot team. That position is held by Ashok Elluswamy.
Oh. Well that puts a different spin on things then. Karpathy said he wanted to sharpen his technical skills. He might have left in part because he felt he was too far from the action, since he was at least 2, if not 3 levels removed from the actual research and implementation work.