Another possibility: Women in poorer countries enrol in CS out of necessity. In wealthy countries, they have more economic freedom and there are more jobs available higher up on Maslow's Hierarchy, so they enrol in what they actually want (which is not CS).
On average.
Several of my friends in CS said their parents wouldn't have supported their college education if they were getting a humanities degree, with the possible exception of law. Even business was unlikely.
* counting South and West Asian too
(1) https://www.forbes.com/sites/amyguttman/2015/12/09/set-to-ta...
"Women make up 48 percent of internet users, 45 percent of cellphone users, and 23 percent of mobile app developers in Iran, Telecommunications Minister Mohammad Javad Azari Jahromi said here on Sunday."
I can't seem to find stats on the aggregate gender breakdown of software developers in Iran.
There is no person on the planet who's advocating for DEI at senior level positions in advanced fields and no changes elsewhere in the system... obviously.