Saying that he's actively disrespectful because he doesn't agree, and then saying he can't be nice if he's not made to feel happy may be constructive to him personally, but not to the project. As he's done in the past several times, he wants changes, he wants his changes, and he's going to act this way if he doesn't get them.

I used to do this when I was a child and didn't get to eat candy.