A bunch of the people present think that they can hack systems. And have read articles about pickup artists and have come to the theory that what women really want is a guy who has the balls to be up front about what he wants. So being over the top seems to them to be a way to hack human relationships.
Maybe there are some women who respond well to that. I don't know. I've never had a reason to try to act like that. But even if a hypothetical minority of women will respond well, the vast majority simply won't. And you'll leave a trail of offended people behind you.
So overconfidence combined with stupidly wrong theories about what women will respond to, and a complete lack of respect for feelings hurt lead to over the top jerks. There are not a lot of these. They are probably a very small minority. But even a small portion have a disproportionate impact on the experience that women will have.