What we need isn't necessarily centrism, but lowered emotions. Emotions are what skew reason and then catch like wildfire. It happens that they tend to push people to the extreme ends of the political spectrum, but that itself isn't really the problem. It's not about sheer distance from the center, it's about voting based on anger and hatefulness and fear. Anti-fascists in Nazi Germany would've been "extreme" relativ…
Attacks on morality and value judgements in politics often take the form of, to take an example, Sir Humphrey’s utterances in Yes Minister. Government, in his view, is about order, and the prevention of chaos. Hacker, the minister, suggests that it is about doing good. Why is Sir Humphrey so scared of chaos? His fear thereof is the same sort of fear that drives morality; we might even call it a moral belief. It is not an implausible belief—chaos has its problems. Most of the time what seems “objective” is no longer on demanding a further reason. “Lowered emotions” should not really be the end; a sensible method of dealing with competing emotions is the need of the hour.