Good points made but the supposed power of the caregiver of the children is not very recognized outside the front door. There is emotional power but the tax departments of most countries look at the role as lesser, dependant, subservient. I am grateful to the gay rights movement for daring to challenge that assumption because clearly there is a sense of equality, interdependency and respect there. In many heterosexual couples we see the same functional sharing of finances, with sometimes the man in charge but often the woman actually handling the accounting but governments are often blind to that sharing. The 'change' we need is to value both roles, the earner of higher income and the earner of lower or no income for the couple thinks they are equal and so should the tax department.
The term 'wife' is very controversial. In traditional marriage vows to now pronounce someone 'man and wife' this made 'wife ' sound like a possession while man was stand-alone. Now we say husband and wife or in the case of gay marriages some variation but the relationship is defined instead of just gender. How can we change the social status of the lower earner? By changing the word 'work' to include unpaid labor, by talking not of working mothers but of mother in the paid labor force, by speaking not of stay at home wives but of women who work in the home. We can make the change to respect with financial recognition of each role, one getting salary and the caregiver getting tax benefits for care work, birth bonus, mat benefits, universal family allowance to age 18, pension benefits for the caregiving years. We can remove the assumed dependency of the role at home and give it its own dignity, reducing vitriole at time of marital breakup and reducing financial tension within a marriage too. Along the way we also end child poverty. Not a bad deal when you think of women's rights advancing but then women never did seek rights just for the sake of it - but because equality has an effect. The care role matters to kids and society. Therefore we must value it.