Yup, I think there’s no big fuss about this in Korea. However, issues like this (things like misogynist, sexist comments, fat-shaming, racist comments, slut-shaming, etc.) are serious issues for International K-Pop fans. More often than not some people found the highlight of those issues better than Koreans themselves.
To me it’s because there are so many Korean cultural values clash with majority International fandom’s view (things about skinny versus fat, for example), and this issue is no difference. Remember how the Dream Girls’ rendition by TvN got serious backlash from International K-Pop fandom (that made SNL announced up their apology) when it didn’t get that much of controversy from Koreans themselves. It’s the same with this issue IMO.
Child abuse is a sensitive issue for people around the world, there’s no doubt. However, some people are more sensitive than the other, and they’ll tend to react towards it based on their own’s values. Each person is entitled to their own opinions, though, I think. :)