Difficult to control for the effects of "building toys" such as Lego being primarily marketed at boys. These types of toys help train this kind of spacial awareness from an early age.

See also early computers being marketed almost exclusively at men and boys, potentially being the cause of a major drop off of women in computer sciences in the 1980s: https://www.npr.org/sections/money/2014/10/21/357629765/when...