Well, I don’t get how skin colour matters here, of course excluding pure racism situations?
There are people with high self confidence, but still just stupid, in that case the ego might not be helpful (but I think it is anyway).
By comparing two people with same skills and different self confidence I believe that person with higher one will be more successful, as you said actually.
The problem with different genders education is a problem indeed, but it’s separated problem than so-called worse treating women in IT… I just can’t see it, moreover I witnessed a lot of situations where someone really wanted to hire woman instead of man to the company. Because of different point of view, behaviour, atmosphere maybe. Women work harder in IT, are more accurate. But these women on interviews just couldn’t sell their skills… And it’s not fault of recruiter.