The problem is the social unrest will be uncontrollable, and among their solutions will not only to be to micromanage the population, but also adjust its numbers by force.
So murder drones will just be sent to cull the masses down to a manageable number. This is the robot future Randall is concerned about in XKCD 1968.
Imagine if the police dogbots killed people and we couldn't question why, nor had the power to resist. This is a problem being considered by AI ethicists. Also that AI will develop scarier ways to cull the population, possibly instigating the demise of their operating end users.