What you say is true, but there are still cultural differences regarding gender roles and Japanese women tend to be more traditional in that regard than American women. They are much less likely to embrace ideas like single motherhood for example.
Yes, but you must agree we aren't living in 1975 anymore, and those concepts and values (or let's say, 'lack of values') have grown dramatically in the last 15 years for Japanese females. (Single motherhood, staying single, learning no conceivable 'home' skills, overeating, expecting too much from men and not giving back (i.e. getting spoiled and "Westernized"), etc.