You’re misunderstanding. You cannot disagree with a battering ram—and that’s what Trump’s tweets are, at least often. Other times, they operate like a carrot on a stick, drawing people through the world through manipulation. But don’t be mistaken into thinking that Trump’s words have any truth value, such that a person could begin to refute it or disagree with it—his words aren’t false, they’re just abusive or exploitative.
The author isn’t advocating that Twitter suppress Trump’s expression because she disagrees with him, because there’s literally nothing to disagree with—it’s rather that there’s a hostile force that must be resisted, and Twitter bears both the capacity and the moral imperative to resist.