It seems everyone with a column and an opinion has weighed in on the Trump town hall on CNN. Actually I'd guess CNN got what it wanted ... what it hasn't had much of lately: viewers. Of course progressives, including those who work at CNN, are furious that he was given a platform.
Trump's superpower is he attracts eyeballs, he makes news, he knows how to make the story about himself, and like it or hate it, he is really skilled. Give him a microphone, a camera, and an outlet on which to post the result and he will drum up an audience. He is a performer and he loves the spotlight.
He lives rent-free in the heads of both progressives and conservatives, though for different reasons. In spite of their dislike, the media can't resist covering him while the most powerful way they could oppose him is to act like he doesn't exist. But he attracts eyeballs and clicks and the media live for those because viewership drives advertising rates.
The irony of their inability to ignore him is massive.