I've been on it, never once felt a lack of empathy, or forwent my principles. If that's happening to a person, it's likely a mask is just being lifted.
But then, I'd also agree there would be loads of cases where it is a mask being lifted, but isn't that the point? Is there a meaningful difference between "revealing one's true self" and "being robbed of an essential part of humanity" when the outcome results in the same antisocial behavior?