It's because in poor and conservative countries women must choose a high paying job if they want to escape oppression and arranged marriage.
However, the more egalitarian and wealthy a country is, the more women are free to choose which job they like most and they are not so interested in Engineering it seems.
EDIT: Ha, looks like this is just a Jordan Peterson false claim. Women seem to be strongly represented in science and engineering in developed countries. https://bigthink.com/strange-maps/women-in-science/
However, the more egalitarian and wealthy a country is, the more women are free to choose which job they like most and they are not so interested in Engineering it seems.
EDIT: Ha, looks like this is just a Jordan Peterson false claim. Women seem to be strongly represented in science and engineering in developed countries. https://bigthink.com/strange-maps/women-in-science/