My POV:- like, i wasnt super-into grunge when it became a thing- my jam ard then was indie/alternative like Suzanne Vega R.E.M., Tori Amos n maybe Kate Bush, plus some Eurythmix n Mike n the Mechanics, even Tears for Fears. But i did like Nirvana's 2nd studio album a lot n played the cassette alot. Also Gin Blossoms n Blind Melon too. Not so much Pearl Jam, Soundgarden, Alice in Chains or Stone Temple Pilots. But thst era ended n i felt no regrets. Even if it overtook the alternative/indie acts i liked from the 80s n relegated them in the public/media attention. Then 90s boy bands n girl power came n went.
My point being there's cycles n trends come n go.
I believe ill always love kpop, or at least my faves. Whether idols n big 3 will dominate in SK n globally, who knows.
You shd just listen to ur faves n dont stress 2 much abt kpop ending. In 10 yrs the teens who r 2 yrs old now will make Billie Eilish n i dunno who's hot with the tweens now, phoebe bridgers? seem outdated or old school/quaint relics.
Music for youths(12-15 yr olds) will always be a little mystifying to those not of tat age, tho i can appreciate Billie Eilish, im sure its not in the same way a teen perceives her music.
Just you do you, as the new saying goes. Dont stress if kpop ends n find sth tat gives ur life meaning, if u can.