> It says that being a married woman with offspring leads to a lower expected salary.
No, it doesn't.
It says that there is a correlation between being a married woman with offspring and a lower expected salary.
https://en.wikipedia.org/wiki/Correlation_does_not_imply_cau...
Furthermore, if you even had read the article you would've noticed the bit where it says "Weinberg says that the data cannot identify or tease apart factors that might explain why married women with children earn less — among the possibilities"