hmmm....Mariah Carey's All I want for Xmas is You charts every year around Christmas I wouldn't call that kpop
there's also a lot of western artists that chart well if they have a popular song but I also wouldn't call that kpop
I agree that kpop is more of an industry as oppose to a genre
that is true but there's also certain people what would categories it and for some people kpop is unique and part of their hobby and they want to make sure what is kpop stays kpop if that makes any sense...
If Mariah Carey would live and work in Korea, then 'All I Want For Xmas' would be a K-Pop song (probably parts of the lyrics would be in Korean language too). For the Korean market, the song would probably sound different too.
An example for a Western artist that is a K-Pop idol: AleXa. Alexaundra Christine Schneiderman, born in Tulsa, Oklahoma. She lives in Korea now. Of course, if she would still live in the US and release her songs there, she wouldn't be a K-Pop artist. On the contrary, there's Rina Sawayama. Born in Niigata, Japan. She lives in London, works in London. Would you call her songs J-Pop?
Yep, I don't like categorizations in music. For myself. On the other hand, if a friend tolds me something about Brit Pop, I know how it might sound. If a friend talks about K-Pop, I know that this music most likely sounds different than Brit Pop. Such sorting of musical genres helps to describe a specific music style. But in my private, when I'm alone and I want to listen to music, I don't think: "I want to listen to K-Pop now, then I want to listen to US-Pop, then I want to listen to J-Rock!" Instead I think: "I want to listen to aespa, Lana del Rey, King Gnu."