Why? It simply notes that there is more than one category of men- that gender is not strictly a question of genitals and biology, and never was- and I am a cis-male; I use the term, as do most of the cis-men I know, out of simple human respect- we're all owed at least a baseline level of respect and decency- towards all types of my fellow human.
Where is the hatred? Is it hatred simply to be inclusive and accepting of everyone's truths?
And what could possibly justify anyone announcing that they will simple never show respect to an entire category of people?