Girls on film

Where are they?

What I have long thought to be so regarding female roles has been shown to be true (in a study by Geena Davis's SeeJane organisation) that girls and women are under represented in children's films. Why is the Slinky Dog or the dinosaur or any of the minor characters except Bo-Beep in Toy Story a boy? Why is Princess Fiona the only significant female character in Shrek? Why is Spirited Away the only animated film I can think of from the 21st century with a female lead?

PS It took me ages to realise "a dope role model" was a compliment.