Idk, it’s just odd to me that you feel you can make such a broad statement. Now more than ever, is a vast multitude of sounds and influences becoming popular at the same times. There’s more access to music than ever before that I’d even say that there’s no such thing as a Mainstream. At the very least, musical trends in the way they have manifested before have fallen off in favor of diversity. BTS isn’t massive for the same reason the Eilish siblings are, or Ed Sheeran, or the Weeknd. All the One Direction boys have very different musical careers and niches.
Not that you have to like all of it - I certainly don’t and am just trying to use identifiable examples - but there’s less commonalities between all the music that gets radio time than there was in, like, 2008. Our generation were the ones who said We Were In The Wrong Generation then, and now we’re the audience being catered to and actually making the music for the charts.
It also looks like you’d absolutely enjoy way more rap music than like the 10 songs you listen to. You clearly just don’t reach out of your comfort zone enough. At least enough to realize what you really dislike is Trap and/or Mumble Rap