Unfortunately I have to hear about this shit from a Korean wife, but Korean stuff is not as popular as it seems. It's heavily driven by bot activity to a hellish level, something Koreans call 'sajaegi'. We know this because South Korean culture is crabs in a bucket behavior on steroids. Nearly every Korean president gets jailed, nearly every idol or singer has their career destroyed by dumb shit that would be a giant nothingburger in any other country, such as "this person was mean to me in high school", etc.
What this leads to is that every time these media groups (movies or Kpop) start having problems with each other (which is very very often) they are very quick to start publishing documents showing that each other are heavily botting any and all engagement that goes on. BTS for example was found to have around 85% of all their engagement being fake.
It's basically Snyderverse but for fucking everything in Korea.