There is nothing wrong with girls or boys wanting build stereotypical applications. Or augment stereotypical hobbies with code.
It is the assumption that it must be those stereotypical topics to get them interested that the author is arguing and I am supporting.
Even you said above you didn’t want to join the coding club because they were, in essence, doing stereotypical boys activities. If they had offered gender neutral activities it might have been different. If they offered stereotypical and gender neutral activities it might have been different.
I want to offer lots of options so that people can find the ones they resonate with.