Here's a question: how can an AI tell whether you liked the game it made? You can't just measure engagement: you'll end up with something addictive, but not necessarily something you'd enjoy playing long-term. Asking the person directly might work, but it's easy for people to lie if there's anything actually at stake (e.g., the tactical way some Steam users give low ratings to "punish" developers).

Here's another question: what distinguishes an AI optimizing engagement from a corporation optimizing engagement? Doesn't Facebook already embody an engagement-optimizing process?