i think you are making a simplistic meaning of that study as it is reported
I found that the tendency for women to marry up in income was greater when they married down in education: Women were 93 percent more likely to marry men in higher income deciles than themselves among couples in which the wife had more education than the husband than among couples in which the wife had less education than the husband
When compared with couples in which the wife had less education than the husband, the tendency for women to marry up in income was 54 percent higher among couples in which both spouses had a high school education, 31 percent higher among couples in which both spouses had some college education, and 23 percent higher among couples in which both spouses had a college degree or above.
From men’s perspective, although men have placed more importance on the financial prospects of a potential spouse over time, some studies have suggested that they may value women’s high status only up to the point when women’s status exceeds their own status. Thus, men may hesitate to form marital relationships with women who have both more education and higher incomes than they do
the study did not explore the reasons so you are doing something the author herself did not do. but note: it looks to me as though fewer better educated women seek to marry up than lower educated women. its possible it has something to do with male views about status and power and no females. maybe income makes up for educational level - conferring an equalising effect of some sort for both parties. maybe what seems to be a desire to have economic security in childbearing years is relevant. maybe maybe
