This is true especially regarding divorce. Biasing divorce renumerations overwhelmingly towards one gender has greatly weakened the shared financial incentive to keep families intact.
In today's society, what's fair is for the non-custody parent to help support the children by reimbursing the custody parent. Or in cases of joint custody, the one with higher income reimburses the one with lower income. Which I believe is the way it's done in my state.
Custody of Infants Act 1839. Prior to this, men both "made the money" and received custody of the children.
https://en.wikipedia.org/wiki/Custody_of_Infants_Act_1839
FredW