I am interested by the gender split of viewership here, and wonder how heavily the various factors of intrinsic gender differences in interest, societal perceptions of Lego as a boy's toy, and confounding factors ("Dad set up the YouTube account that child Emily is watching from", Mom has less leisure time) contribute to each of these. I also note that the themes of the most popular videos ("BIG vortex", "tank" "car") are often associated more with traditionally masculine than feminine themes, perhaps making it hard to pull any Lego-specific insights from this.

Certainly my nieces are no less interested in Lego than my nephews, and growing up my sisters weren't less interested than my brothers (although there did seem to be a difference in focus in construction vs Sims-like play).