Believe me, I know he's a troll, and he's very good at being a troll. However, sometimes the smart kid who can articulate is what you need rather than the kid who audibly farts in class during final exams.
When Elizabeth Warren is pitching Medicare for All and the media is doing everything they can to make it sound great, we need an adult, not a troll. We need someone who can explain to a bunch of people who are constantly told that socialism is great why it's a bad thing. That isn't Trump, and frankly, he has never played that role. The ideology and rhetorical discipline simply aren't there.