"The household structure of a 'breadwinning' father and a 'homemaking' mother is a cultural phenomenon, not a biblical one"

Titus 2:5 “keepers at home” has to mean something. Given Prov.31, we’d be off base to say it means wives never work outside the home. But the idea that there is a “homemaker” (oikourgos) is not merely tradition. Tradition informs us as to what the role looks like, how it works in a well ordered home. But the core idea is a biblical one. See also 1 Tim. 5:14. Though that passage speaks specifically of young widows, it arguable directs them to behave like married women with respect to keeping a home.