If I were to guess what it could be, I would assume that the biggest reason is due to republic of Korea having a mixture of the worst of two worlds. Essentiall

If I were to guess what it could be, I would assume that the biggest reason is due to republic of Korea having a mixture of the worst of two worlds. Essentially its conservative/collectivist culture is counter productive to those who wish to establish themselves and have a family (enforcement of gender norms, restrictive demands towards the individuals of said family, attitudes towards minority families such as lgbt and general view stomping down a liberal individualism). On the the liberal/individualistic side of things, the issue is that the work towards equaility is such low hanging fruit, any change is seen as unfair and threatening by the male population, but also liberal ideals do only tend to want to focus on female issues, in fact it's said it's one reason the current president of South Korea won thanks to the previous government work with feminism while ignoring the male side of issues. And individual expression in this case is essentially only in practice seen as a means to get an edge in the rat race that is get more money or status (social or romantic), which at some point causes young people to see relationship more as a burden (as stated before) and debilitating (essentially the low hanging fruit of dating is gone, thus it fuels a feeling of doubt of how you can date and actually be together). Mind you this is a cultural phenomenon in much of Asia.