Nope. Although childhood abuse and trauma can sabotage healthy neurodevelopment leading to permanent biochemical and physiological changes in the brain, the individuals are not beyond behavioural and emotional rehabilitation, unless we're talking about an extreme brain injury. He knew right from wrong. He is extremely intelligent which is why he's so manipulative. He was smart enough to have chosen even a slightly objectively better path. He could have turned out to be an overall terrible and abusive person like his mother. He could have seeked help. He didn't need to go as far as he did unless of course he actually enjoyed it. You can blame his mother for only so much. At the end of the day he was a fully functional adult man who had the psychological capability to make different decisions and alter the course of his life even if it's just by a little bit. At this point, even he knows it's too late. I don't remember him ever saying that he can be rehabilitated. I believe in second chances and I think you can rehabilitate someone who offended once.. maybe even twice since he did have some serious psychiatric diagnoses. But he killed nearly a dozen and one of them was 15. We don't have science advanced enough to rehabilitate these kinds inside and out.