It's always possible for two to gang up on the third one.

Polygamy only works when there aren't enough men. Polyandry is practiced when there aren't enough women. But in both of those cases, it soon becomes a power relationship in which the single spouse of one gender is more or less the owner of the multiple spouses of the other gender.

Child marriage, especially of the arranged kind, is an abomination and a form of child sexual abuse. Period.

If you ascribe hostile intentions to the fact that men are no longer able to dominate women using the legal device of marriage, then I guess you could say it's a war. On the other hand, men have a more robust history of behaving badly in marriage, especially in the practice of spousal abuse, larceny of common property, and desertion. So, after many centuries of this, women have begun to take more control of their own destinies.

Men who behave like civilized adults often find themselves in good marriages, or at least friendly ones, and not under attack at all. They should give lessons. As for the rest, they can stop pouting, learn to control themselves, and grow up.

How this relates to homosexuals, I will leave to the religious extremists. I'm sure they will find a way to blame the Others, because it surely can't be Our fault.