Emotions can be used to get people to do things both "good" and "bad" either intentionally or unintentionally. Think about people who are less emotional (i.e. men), oftentimes they can get stuck in objectively shitty jobs with less freedoms or political ideologies that aren't actually working for their benefit and yet they still just go along with it. Whereas other more emotional people (women) wouldn't tolerate unacceptable working conditions or poorer quality of life quite so easily.

and to add, is the purpose of less emotion in order to make you more susceptible to being used?