Jon Stewart is often a terrible interviewer. Especially when he either hasn't found any respect for the guest or when he likes the guest so much they can't take the promotional point of the interview seriously.
In one case he fails to address the perspective of the guest (which means he emotes a lot and asks questions they don't answer) and in the other they more or less just smile knowingly at each other for 5 minutes.
I suppose another way to say it is that much of the problem is that he tends to make the interview about himself.
What you say is certainly true when he is interviewing entertainers, but I do think the parent is correct: if he's got a serious guest on and they are discussing an issue Stewart cares about, he really lets them use the time effectively. He mostly stays out of the way and just helps them stay on topic.
Promoting his agenda through guests is his reward, I suppose, for stumbling through so many interviews with vapid celebrities.
Yeah, the less antagonistic serious interviews go okay. That's why I was so specific about guests that he can't find respect for.
I also don't think he is really stumbling through the celebrity interviews, he's playing himself as above them. When his (lack of) relationship with the guest makes it so that won't work, the interview goes along just fine.
In one case he fails to address the perspective of the guest (which means he emotes a lot and asks questions they don't answer) and in the other they more or less just smile knowingly at each other for 5 minutes.
I suppose another way to say it is that much of the problem is that he tends to make the interview about himself.