[Tozen]

While aspects of what you are saying is true, arguably, South Korea's problems are deeper than that. Choices are also limited by tremendous amounts of nationalism, racism, and xenophobia. This goes way deeper than people know. South Koreans are not really free to socially associate, date, or marry who they want. They can be ostracized or shunned for doing so, and this can have very restrictive barriers and limitations. Few have the personality or character to overcome this. What's acceptable can create such a narrow range of choices, on top of just female hypergamy or materialism, that few can ever attain this.

And for nationalist (to be polite), it can be very acceptable that their "race" dwindles to the very few, as long as it's "pure". For those not familiar with that brand of nationalism (to be polite), this can include other Asians who are not Korean or don't "look" Korean.