I wrote about IU being at the back of every single act in Korea, and she could strike anyone if they were out of Korea for a long time.
Her presence significantly skew KPop into a bad way, since because she is being there, all the KPop acts have to care about Korea at least once in a while.
It is significant that most acts in the 3rd generation who became really famous got their starts in 2016, when IU was not singing.
That aside, I have read quite a lot about disgruntled BTS fans in K-O-R-E-A who were angry that BTS did not release K-O-R-E-A-N songs, and only cared about foreign fans. This frustration by Korean fans did not hurt the envious younger K-O-R-E-A-N men who fought tooth and nail to send the members to the military.
With the resumption of concerts around the world, more acts will emphasize their non-Korean activities, but because of what happened to BTS, K-O-R-E-A-N promotions, even if they are not really productive (I personally think for acts which are quite relevant around the world, they are a waste of time and money) have become mandatory when these acts release songs. (Songs geared for a specific country would not be part of it, but still.)
The KPop boom around the world never really solved the problem of the K-O-R-E-A-N fans which could not be abandoned entirely, because to promote a company's newer acts, they had to gain fans in K-O-R-E-A first to go anywhere so if a company abandoned K-O-R-E-A it could kiss goodbye about the future of its next act.
JYP tried NiziU, a Japan-only act, and SM tried some Chinese-only acts, but they have little reach outside of the countries they operate in.
It is a dilemma which was never solved; while Korea is needed, it is not needed at the same time. Its aging population follows trot, originating a genre of music popular in Japan during 1930s (although Korean trot has incorporated a host of other elements all the way to rap), while all the KPop acts have never been able to bury a certain domesticist from the minds of the K-O-R-E-A-N-S.
Which will probably limit the reach of KPop acts around the world, since all of their world tours will probably have to include Korea at least once and that means they will have to release K-O-R-E-A-N songs once in a while and promote, robbing the time to work in the overseas with more profit.