First, an idea, while unpleasant, may well be correct or true, in which case we gain insight by being exposed to it. And even if it is only partially true, it can help us reach a more complete understanding of the whole truth. Second, even if the idea is simply wrong, we benefit from hearing it and having to think through why it is wrong. This connects to the third point, which is that even true or useful ideas need to be contested and re-evaluated if they are to remain fresh and avoid calcifying into rigid dogmas. – Quillette