In Korea, which is where the Kpop industry is located, it’s just koreans. That’s it. Of course, they have foreigners in their country, but there’s not a sense of Asian unity that you see in, for example, Asian-American communities (diaspora)or in other western countries where asians live.
The reason that companies scout idols who aren’t koreans is because some asians can fit into the Korean beauty standard just as well as Koreans.
They don’t care about Asian representation. If they did care, they would be scouting Vietnamese, Khmers, Lao, or Malaysian idols, but they don’t because it’s not their intention to represent Asians.
It's just a pipe dream I have that companies should suddenly scout asians outside of East Asia. We will see nationalities outside the ''Kpop norm'' like we already have with Fatou in BlackSwan, Dita in Secret Number, upcoming Hanbin in Yuehua's Tempest, but not scouting where they come from.