But keep in mind that he may have traded one obsession (killing people) with another. Just saying…
There is somewhat of a difference between an obsession whose fruit is evil and one whose is good.
He has seemed consistent about his faith and appears legitimately remorseful, living to atone for his deeds.
If he is sincere, then having murder on his soul has surely been a heavy load. If he's obsessed about compensating, that's how he deals with it. Many would say tough cookies his victims don't have a life at all, but he can't go back in time. It's what it is.
The Messiah is the guy who can love the unlovable who have committed such horrible acts that noone in society would want anything to do with them ever, just in case.
Perhaps David Berkowitz has been able to reach the unreachable and unlovable, because he himself is the last person anyone would love. God knows the heart.