I'd have to disagree...
I think this problem exists with all teachers towards different groups of students. Again, it's not just boys affected by this sort of thing, what if you're hispanic and the teacher just doesn't like hispanics?
Burying our heads and saying that the problem doesn't exist won't help us to make progress towards better outcomes. Which is the ultimate goal here.
We need to answer the question of how to help all students successfully traverse these kinds of obstacles? Answering that question and integrating such training into their educational practice will not only help them in class, but it's a skill that I have to believe will serve them well throughout their lives.