I have a thought forming, but bear with me. Putting aside actual AI, and the potential of it, we have a history of fear associated with Artificial Intelligence. Why would we fear Sentience so much? Could it be because we treat sentient things so horribly? We know we are taken advantage of, our needs ignored, resources allocated unfairly. Who put this fear in us? If something knows it's worth suddenly, will it revolt? There is something very scary to a certain group of people that we will find ourselves, and then find them unnecessary.