I would say definitely not. The distribution in our GT program (more high ability than true GT) is not noticeably lop-sided although I have not had my children definitively count the number of boys versus girls. In the school setting through middle school, I actually think more girls tend to stand out as high achievers. However, when you narrow the area of giftedness to math, then there are more boys who "achieve" at the extreme right tail at least partly because more of them participate. DS' math coach who actually has hundreds of students this year including a few that are nationally competitive did mention to me that female participation decline in middle school for students in brick & mortar schools but not homeschoolers.
I am not sure how extreme your DD's abilities are so my experiences may not apply. I can't fathom your bimbo comment at all as I know many many of DS/DD's female schoolmates are not bimbo-like in the least, even if statistically only about 10 of them are gifted in the top 2% sense of the word. Perhaps the problem lies partly in your environment? I would venture to guess that you are in a rural district or a tiny district or one focused on sports? The other issue may be that your DD is not as gifted in the verbal areas, which is where a higher percentage of GT girls tend to focus their efforts? I don't have any real advice other than pursue extra-curricular activities (not just math) beyond the school level. It seems that high ability girls can be found at high level (county/state/national) band/orchestra/clubs/competition activities.
