It's like the mental illness argument with school shooters. Yeah, they're obviously mentally ill. But they're not doing it BECAUSE they're mentally ill, they're doing it because they didn't get the help they needed and their mental illness causes them to continue getting worse until they snap and act out on those feelings.

Mental illness isn't the direct cause of any of his behaviour, but it's definitely exacerbating his paranoid delusions and self-aggrandizing behaviour.