It's true that the term harmony applies when it comes to Bangtan.
Because they have a hiphop concept, so they have a lot of rapping in their songs. But instead of compensating with poweful vocals, they decide to push soft and emotional vocals instead. They don't include so many high notes so people think that they can't sing..
I'm pretty sure they have no intentions on switching to powerful vocals, I think that right now, they found the best balance they could achieve. It's a shame that people are calling them talentless
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