> I hate how he talks, but he seems to be an effective communicator if you only judge by results

Looking at Iran situation, absolutely not, results of Trumps communications are pure disaster. Looking at tariffs situation, absolutely not, results of Trumps communications are pure disaster. His communication is masterpiece of ineffective communication.

On the plus side, he is emotionally pleasing to certain kind of people and he is effective in bullying and humiliating close ones. If those are the goal, yes he is effective. But, he cant do much else.