Should people be held accountable if there is no free will?
Of course! In fact, the “No Free Will” argument is the best possible argument in favor of holding people accountable. Think about it in terms of influencing future behavior rather than punishment for past behavior.
Yeah, accountability is more a matter of behavior modification than it is objective morality. If a person is acting anti-socially (no pun on your name intended) then his behavior needs to be modified so he can live in society without disrupting everyone else’s life. If his behavior cannot be modified, then he’s locked up for life or institutionalized, etc. The issue is how to do this without impinging unnecessarily on freedom, and this is always a balancing act. But if you are considering behavior in the absence of deity, then there is no objective, universal morality, and you have to dance the moral relativism dance. And dancing always requires good balance.