I hate to get into these discussions (even though I somehow do :-) ). I can give you my impression having lived here for about a decade, though.
In Japan traditional gender roles are a lot stronger than they currently are in the west. Trans gender (and similar -- I apologise if I am getting the terminology wrong since I'm largely ignorant of appropriate language) culture is widely accepted in the media, but not terribly accepted in wider society yet. The idea that men and women are the same is antithetical to Japanese culture. If you think about gender roles being 1950's American ideals (think "Leave it to Beaver", etc) you'd be pretty close.
By and large Japanese people like it this way. Feminism is a dirty word, even amongst women as it is considered to be "too pushy". Things like wage parity are very slowly being addressed. Sexual harassment is being addressed at a much quicker pace and these days I think the vast majority of people consider it to be completely unacceptable. 10 years ago, when I first came here, I think the attitude would have been more, "It's not good, but what can you do".
When I was teaching English at the local high school, the vast majority of female students said that their ultimate career goal was "housewife/mother". Some of my expat colleagues found this horrifying and even lectured their students not to "waste their life". This caused a minor uprising as Japanese people regard "housewife/mother" to be a very important role in society. Many students were upset about the message they were getting.
Young women in Japan have a strangely powerful position in society. Women in Japan get married very late compared to western countries. This is one of the reasons for the low birthrate. Usually they live with their parents and contribute little or nothing to family income. They work until they decide to have children (usually in their early 30's) and then retire from work. As a woman, your 20's are where you are most free -- this is contrasted with men, where your 20's are where you are least free because you have to get your career going.
In this way young women in Japan control most of the disposable income -- and you can see that in the types of luxury goods. Fashion, makeup, etc are very popular and very expensive. Young women also travel a lot and travel agencies are geared towards catering to small groups of young women.
When women get married, they often have children fairly quickly. They assume the running of the household and handle all of the finances. It is completely normal for men to not have access to any money other than pocket money given to them by their wives. Lately people have credit cards, but again 10 years ago they were quite rare (especially in rural Japan where I live). Men usually didn't even have bank cards. For men, life is work to provide money for the household. For women, life is running the household.
I hope it's a little easier to see that with that perspective being a housewife/mother is a fairly good life. Many young women choose this life because they can't see themselves devoting their lives to a meaningless job that just provides money. You could easily ask what the purpose would be, unless the husband is at home looking after the household.
There are more "househusbands" than there used to be. As I work from home, I see them running errands occasionally. Often they tend to be of foreign origin with Japanese wives. A few years ago the mayor of Osaka actually took paternity leave and stated that all fathers should do so. It resonated well in the circles in which I travel, but I still don't see anyone else taking paternity leave. Maybe in a few more decades.
Generally speaking, men like "men stuff" and women like "women stuff". Being cute and girly is considered a good thing if you are a woman. Being gruff and tough is considered a good thing if you are a man. I don't know if that will ever change (even though I know many people who find it objectionable).