One of the reasons out of many is definitely the “pregnancy boycott”. There are some young women who are saying “no” to getting pregnant and having children, or even getting into relationships at all. One of the reasons is the insane work culture and the unrealistic expectations put on women that they should to be able to put insane hours into work AND do all the housework and childrearing on top of that. They’d also be heavily judged by their in-laws, etc., and so there’s a lot of negativity and sacrifice that comes out of becoming married and getting pregnant.
Another is to boycott against the sexist treatment of women by men. Around 60~70% of women in their 20s consider themselves to be “feminist”, and around 80~90% of men in their 20s consider themselves to be “anti-feminist”. So there’s already a big divide among sexes in young people.
Latest Answers