I have 2 boys and a girl.
I don't count their calories and they eat when they are hungry. However a banana is the average difference in calorie needs between the sexes at preschool age.
Pretty much every parent thinks their mobile baby or toddler is "very active". Hardly anyone thinks they have a moderately active, average toddler.
Your blog does indeed sound incredibly niche - aimed at fans of enforcing gender stereotypes as early and as firmly as possible.
Perhaps you could have a section on how to keep your boy away from the princes dresses/ play kitchen/ dolls at preschool, ways to explain that your boy only likes doll prams because they have wheels, manly boy toys, manly preschool TV programmes (and non stereotyped or "girl" toys and programmes to avoid so boys don't accidentally watch something which might give them girl brain)... Just a few ideas.
Obviously boys shouldn't eat pink fruit - avoid those strawberries, and if he must have apples make sure they're green not that suspicious pinkish red, definitely no pink lady variety, and best avoid granny smith to be safe - still a bit feminine! Load your hungry boy up with some good hungry boy blue fruits, like blueberries... Perhaps a manly hungry boy Yorkie bar if you're introducing chocolate, no girly buttons for a hungry boy...