As a mental health professional (former clinician), I guess I've been thrown into the group that allegedly has consensus on this subject, so I would like to comment.
"Not caring what others think is a hallmark trait of antisocial behavior, sociopaths and psychopaths"
Yes. It is also a trait of other things, such as a balanced self concept, healthy coping skills and some normal personality types such as INTJ.
Pathological or criminal disregard for the rights and wishes of others, in the context of DSM criteria for Antisocial Personality Disorder, is an entirely separate thing from "not caring what others think of them" as described in the OP.