If I'm going to make a generalization, my theory would be more along the lines that women may have a tendency to date people who might not be that honest or respectful. I think women can easily fall into the trap of forming these absurd romantic fantasies that they expect men to fulfill, and that certain men will use this fantasy to manipulate women, with a certain degree of success. I think when men act extremely out of place with this fantasy is a huge turn-off, which might be why guys who don't act like the guys in romantic movies, E.G. those just trying to be themselves and not being manipulative, end up not being romantically interesting.
Women might also enjoy "the chase", and will want a guy who will peruse them; Naturally, this could attract the worst kind of rapey dudes, since this alienates guys who would respect a women's space or choices, so there's some natural cohesion there. Socially, we're still in the fucked-up place where it's expected for a man to ask out a women, and never the other way around, also giving and edge to the rapey, abusive people. Not saying that all confident guys are rapists, only that rapists tend to be overly-confident, or at least would generally be more up for the chase than other guys. I think this hunter/prey dynamic that's so deeply ingrained in society might be the biggest part of it.
I also think that women have a tendency to compartmentalize people. If a woman puts a man in a role in her head, it's very hard to escape that role. I don't think it's limited to 'friend' or 'romantic interest', but also other things i imagine like 'that guy whose good at schoolwork who i can ask for help' or 'that creepy guy' or something. I do think that overall men are more lenient with people moving through these rolls, and taking on multiple roles, and women like to keep people in their original role with little chance for redemption, mobility, or overlap.
EDIT:
Oh, yes, as others have mentioned, it would not surprise me if the whole "i can change him" fantasy played a part.