In such situations: a) HR provides the appearance of some orderly process to settle such situations b) HR provides partial witnesses for settlement talks c) HR produces documentation about the situation to be used to the company's advantage in later lawsuits d) HR creates (beforehand) a net of regulations that a "troublemaker" can easily be found to have violated e) HR shields more important employees (i.e. bosses), because they represent more value to the company f) HR shields larger numbers of employees (i.e. the mob of abusers) against smaller numbers (i.e. the single victim), because larger numbers represent more value and higher risk of complications

Nowhere in the above list I did mention anything about workplace happiness or positive energy or anything. That is not up to HR, and if a "situation" arises it's too late anyways. Good interpersonal conditions are up to all persons and especially management. HR is just there as an executive, to sweep up the broken cutlery and make things look nice and tidy.

It isn't that an HR department doesn't want good working conditions. They are just in no position to impose them, only management is.