This is the equivalent of not teaching chemistry, and then someone who's dabbled in alchemy piping up and saying: "Why bother with all that, it's not that hard, just combine earth and water!"
The reality is that the "assholes" get the hottest women. I put that in quotes because that's the superficial impression, not a nuanced statement. It's valid though. There are women who get married to murderers on death row. These are sexy, beautiful women. Meanwhile "nice guys" are single into their thirties and complaining about it on Reddit.
Even a casual perusal of either anthropology or evolutionary biology should dissuade you from any such silly Disney(tm) approved notions.
Women maximise their reproductive success by partnering with killers. Hunters that are capable of bringing home the bacon, but just short of being psychopaths and killing her and her children. A little bit of violence is acceptable.
Being "nice" and "polite" doesn't work. As a random set of examples, people here on HN will generally acknowledge either Trump and/or Elon as being unmitigated asses, right? They've both had multiple wives and a bunch of kids.
What does that tell you?
Are you going to do chemistry, or alchemy? Magic, or science? Are you getting dating advice from Women's Weekly, or Nature?