Yes, I know she talks about male writers and I understand her points but... she also talks about growing up reading stories and the expectations set up from childhood fiction and I just don't think it's true that growing up as a girl the only female characters we encounter in stories are forgettable supporting ones. For a start, the most famous children's fiction writers have been women, for largely sexist reasons, so what about the tension between views of femininity in novels such as Little Women or Little House on the Prairie or the Railway Children?, the books I remember most from my childhood with strong girl characters. It's not enough to just portray them as the odd tomboy who gets married off ASAP, they're more complex than that.
She may argue that she's only talking about fantasy fiction, which is very possible given how confusing her writing is (conveniently letting her off the hook whenever anyone challenges her about her generalisations). I think it's true that if the stories are aimed at boys, which much fantasy stuff is, they will have boy main characters. But even there that's not all there is - what about Phillip Pullman's His Dark Materials - the main character is a girl, a strong female character. LP is just the age to have read that as a child, it must be, apart from Harry Potter, the most famous children's fiction of the past 3 decades, fantasy, a genre she likes, and yet...puff!...it's like it doesn't exist.