There is a common misconception in the public which associates psychopathy with crime too closely. If you check with the article linked above, it should become clearer. The definition of psychopathy is the absence of empathy. Not all psychopaths are or become criminals, but many criminals are psychopaths. The predisposition exists in a certain percentage of the population, current working theory suggests it is genetic.
How does this relate to a game or VR, where acts not possible or allowable to carry out in reality are part of the content, even by design? Simply by being attractive to those with the disposition. I am not a supporter of those who say violent video games bring about school shootings and other horrible acts. This is a gross oversimplification and doing injustice to gamers. After all, imagination is what playing is all about. But the mental mechanisms are the same in both worlds because the minds of the actors are identical. Specifically in environments where pvp-affine and their opposites get to cross their lines, conflict is programmed, and while that is still part of the game design, the pleasure of a ganker he/she gets from someone else's displeasure is straddling the limit between fantasy and reality. Otherwise it wouldn't be attractive to gankers. Nothing is more boring than to blow up like-minded people all day. But the other side isn't in it for the same motivation. The cultures don't mix, and any attempt to squeeze them into the same room is a design flaw. Therefore we have alternatives, which is good. The fact that a certain portion of people doesn't like such boundaries protecting the rest from being assaulted in this way is telling of their lack of empathy, which is the definition of psychopathy. This is what it is, gross or not.