If you attribute so little agency to people that becoming a heroin addict becomes someone else's responsibility (barring physical addiction in the womb or being shot up at gunpoint repeatedly) then there's little in this world that we can control anyways.

Your conclusion is entirely consistent with the facts. There is little in this world that we can control. It's really important to stop the bad actors from taking the little away from us.

Curiously, what is that little we can control? One could come up with an argument about how we control exactly zero in life. However even if it's true in a way, it might not be so useful to believe that since having that belief will lead to worse decisions (and a lot of psychology research shows that a belief that you don't have control is highly correlated with depression).