John Stewart's Castle Wall

Awhile back I wrote about John Stewart's growing credibility as host of The Daily Show and his curious new designation as an actual political pundit. Given the fact that his show is, in his words, "fake news", I continue to be surprised as he now has a book and is appearing on non-fake political shows such as Crossfire. I finally got a chance to see the clip of his segment on Crossfire where he takes the two hosts to task for not doing their jobs and "hurting America". Now, I never watch Crossfire and have stopped regularly watching Stewart's show due to it's total slide into non-objectivity (that plus it's not that funny lately), but am I the only one wondering where Stewart gets off? I mean, he never stops talking about how his show is a big joke; always hiding behind the "fake show" argument to avoid criticism and pronouncing those who take shots at him as absurd for trying to hold a fake show and host accountable for anything. My question is, why didn't the Crossfire hosts just say "listen John, if your whole show is a joke and it's absurdist to question your journalistic integrity; if you're nothing but a comedian who shouldn't be taken seriously, then why should anyone watching care about your thoughts on, or for that matter on anything at all?" I'm telling you, it's only a matter of time before Stewart makes the mistake of going on a show with a skilled interviewer and gets creamed. Now that would be funny.