At he risk of sounding sexist, when I read this article my first thought was of course they are going to look at boys more than girls. Girls are supposed to be quieter and shy. Boys are expected to noisy and active, if they don't, parents and doctors rush to his aid and try to fix the problem, lest the boy grow up to be different. There's a lot of social politics about how a child develops, especially boys.
Another problem the article points out, is how long it took for girls to be properly diagnosed. They just didn't see the significance of the girls behavior. Again, less attention is paid to girls.
Think I'm exaggerating? I wasn't diagnosed until I was fifty, the psychologist merely confirmed what I told him and despite having friends who had it or had children with ASD, no one saw it in me.
"But you act so normal," they explained when I questioned them. Yes, after decades of imitating neuronormals as a coping skill.
The Lesson here is that adults need to get past gender expectations and pay attention to girls as much as boys or it will lead to the stress of undiagnosed girls struggling to develop or fit in.