PHB doesn't own his own behavior. He blames his loss of control on Dilbert and is trying to change Dilbert instead of himself. Dilbert points out the absurdity of PHBs plans by taking it to a new level..
Dilbert does have poor interpersonal skills but that has nothing to do with his conversations with Dogbert
Interestingly, if we didn't know anything about these two characters, we might think the man with the funny pointy hair could be right. Of course knowing them, he is only half right. Dilbert does of course have poor interpersonal skills. (If he didn't, he wouldn't spend so much time talking to his dog.)