Interesting. It makes sense considering how global acts are. In second gen, it was kind of surprising if an act managed to survive based on the strength of their international fandom alone (ala U-KISS), but now, there are a ton of acts who fall into that boat. I also saw a note that Korean streaming has moved away from Melon for a while now, so it's not as reflective of Korean tastes as it is.
It kind of reminds me of when Billboard changed their practices after Psy failed to hit #1, because they didn't properly take YouTube into account, and "Gangnam Style" was just so objectively more popular than anything else at the time. It just couldn't get the radio play.