Too many people respond to such things with, "well, all they care about is ratings!" But, no, the decisions aren't just made for ratings, and certainly aren't just made *correctly* for ratings. Another one is simply that habits die hard. They're so used to talking about him that they can't talk about anything else. Their sources are all Trump people and John Barron, and it isn't just TV that I'm talking about. Newspapers too.
It was a different media world back then, but they couldn't stop talking about Clinton for a few months after he left office, too.
It'll probably only last a few months, but it'll still be ridiculous.