Ask HN: How could setting an AI's goal to be “increase human autonomy” go awry?

I read Nick Bostrom's book "Superintelligence: Paths, Dangers, Strategies" a while back and found the problems in trying to set a goal for AI to be interesting/difficult. He outlines various ways the goals could be misconstrued by the AI, which eventually leads to human extinction. I think setting the goal to be "to increase human autonomy" might get around some of these problems. I'm interested to hear how people think it could go awry though.