Since joining sndbox I've watched some YouTube clips of life in S. Korea, and they all reflect what you report, except:

Life for a youth in Korea has been dubbed “Hell” by the majority. That is a shocker.

In some respects, as you probably know, the situation is similar here in Germany it terms of the ageing population. Here we have other problems which you don't. As some here say, culturally in 50 years Japan and South Korea will still be Japan and Korea. European culture will be so diluted that for practical purposes it will no longer exist.

This will not change, and it isn't wise to speak of it.

In terms of policy for S. Korea, I could imagine small communities with generously subsidized homes for people with a child who have a second child on the way. Perhaps one of the parents could be offered a part-time job in the community (schools, kindergarten, social services, etc.) as a compromise between stay-at-home-parent, and both parents working.

It is a huge problem.