I would say that men means the male part of mankind, there's a female part (women) and some others who identify themselves as something different. Mankind is a diverse mix, if it were only men, then there would be no mankind. So to sum up, some people are indeed men, but men do not represent all people.
in classic grammar of many languages men forms means also mixed groups and men means menkind at all women including these weird new forms are ugly (i.e. when canadian premier tried to invite a new word humankind or peoplekind) neomarxism is an ideology and i do not see any reason why it should mix to grammar ...
I do not see "humankind" as a neologism; I have often seen it before. I do not understand what using an inclusive term has to do with Marxism, neo- or not. Grammarians may say that "men" includes women as well, but when I hear "All men are created equal" or the like, I don't FEEL included. I would prefer "All human beings..." I do feel included by "Women and men..." or "Men and women..." and do not myself consider either of those phrases "weird new forms [which are] are ugly". Perhaps you might feel differently if you were in the half of "mankind" which is only included by implication.
""Humanity" is just fine, I would say; it's another inclusive word. And there is "human beings". I don't see anything wrong with "humankind", myself... I remember the huge fuss some years ago when some persons at the University started saying "chairperson" to include those who were chairwomen. Those who got their knickers in a twist all seemed to be of the masculine persuasion. I suspected that what really outraged many of them was not the alleged attack on the language, but rather that chairperson was no longer an exclusively male preserve.
One meaning of "men" is "male humans". Another meaning is "human beings [including female humans]". When "men" is used, it is often ambiguous; often which of these two meanings is intended is unclear. For those cases where one DOES mean all persons, not just the male half, "humans" or "human beings" or "people" or "persons" makes it clear that one means men AND women, not just male humans,