Sorry, but you're being extremely biased here. Mistaking assertiveness for arrogance can happen with any outsider in a certain field. It's not related to gender at all, and your example doesn't even argue for it. The project leader could perfectly be a man. What you describe is a problem with people in general, not a problem with women at all...
The gender difference I'm pointing out isn't mistaking assertiveness for arrogance (in fact I'd say this happens more frequently with men, as statistically they end up in a greater number of leadership roles).
The gender difference I'm pointing out is in how those who take offense to the bitch/asshole label push back against that accusation.
Anecdotally, I've noticed its often the case that women will make an appeal to victim-hood ("You're just calling me that because you have a problem with powerful women"), which is something I haven't seen men do. Sadly, they are often correct. But a small portion of the time, they are mistaken, and somehow the specious claim of sexism is particularly odious. That tiny portion of the overall picture is what I was pointing out.
With men, it seems more often that either they shrug off the accusation because they are fine with being an asshole (which is particularly distasteful), or they respond by further turning up the arrogance dial ("I'm not an asshole, its just that I'm better than you").
