The problem with these kinds of studies is they don't recognize any merit in the choices families make. My wife works a 4 day week because schools here get out at noon every Friday (and have PD days a couple Fridays a month), and she'd rather just stay home, and volunteer at the school or get some errands done, rather than hand over most of her pay for that day to child care. For us, this is a sensible arrangement. For the people who created this study, it's a problem to be fixed.
As for the low level of female representation among business executives, the explanation is pretty straightforward. Those jobs require an almost complete dedication. Long hours. Frequent travel. Little time for family or leisure. If you have kids, the only way your family can manage is if your spouse dedicates themselves to the domestic realm. Male executives are usually married to women who will handle those family responsibilities. Women need to choose mates who will do the same.