Unfortunately you can’t change most peoples minds with facts and logic when they are emotionally involved. Using a bunch of facts is sometimes OK when the person doesn’t have a particular stance, but once they believe what they believe it does take nurturing to change.

It sounds like he knows where you stand on the subject, and it sounds like he is struggling to find male role models in his life. If it were me, I would spend time with him and show him I care about him. Also be your best self, show him that the things you believe create a strong, loving, independent person. And the other people he seems to be looking to for guidance only lead to a hateful, sad life. Not that this is something within most peoples means, but therapy was a huge factor in my own political journey. You should also let him know straight up you feel a great deal of regret about how you treated him in the past, be as honest as possible.

You’re right, I do believe the answer to this is an emotional response. And unfortunately you won’t get an amazing answer to that on the internet.