"In 1981, LEGOs were simple and gender-neutral, and the creativity of the child produced the message. In 2014, it’s the reverse: the toy delivers a message to the child, and this message is weirdly about gender.” As a 70s child, 2010s parent: exactly this. https://womenyoushouldknow.net/little-girl-1981-lego-ad-grown-shes-got-something-say/

In the past decade or two, the toy aisle has been used push children of each sex into fixed boxes with a force I still find hard to process, even as a parent who has lived (fought her way) through this.

With (dis)honorable mentions for the clothing aisle and the stationary department.

This would also be my main explanation. Our children have being squeezed and squashed more and more into boxes based on their sex to enhance the bottom line. https://twitter.com/TJVRD/status/1280644234874404864?s=20