You know, I never figured it out. Both mothers (different) and I were very committed to a gender free environment. We all had too many pressures growing up and we wanted to raise children without them. Well, with less than we had experienced.
I remember the first time my son pulled it on me; I was really? How do you know this isn’t a toy that another boy brought in. His look was clear, very clear. Dad was stretching, reaching to fill in the facts to match his world view. Which wasn’t his world view.
Seven years earlier with my daughter I remember asking if she wanted a truck or car to haul her dolls around. Yep, same look. Later in life that came with eyerolls from her. Her daily life wasn’t totally in my view so some normal attitudes might have filtered through. But, she is an adult, with children and still very much a girl; In the sense that enjoys looking like a woman and plays video games with her own adult children.