I'm thinking more about the ones that have maybe been kpop fans for years.
Well... I have been that since 2012.
But when I listen to some kpop song that I haven't listened to in a while, and I end up understanding some words or stuff that I didn't know back then.
And also knowing some words but not understanding the meaning of those words.
I'm not fluent in Korean, but as I have gotten older, I have gotten a bit better at that language.
Or at least I think I'm better at it than I used to a decade ago.
I think it is the same for some other languages like Japanese, Mandarin etc...
Like I could listen to some Japanese song that I enjoyed as a teenager and be like "Oh, I know that word now"