Also this article talking about their global dominance is from 2015.
Big Bang’s Global Influence: How to Build a Boy Band That Lasts
The K-pop quintet’s new tour documentary will premiere Nov. 11 on streaming video service DramaFever
www.google.com
So how did BTS introduce kpop and become popular with no help when BigBang, PSY, and even SMTown was selling out concerts across the globe?
Even people who didn't listen to kpop back then knew who BigBang was. They even inspired several members of BTS to become singers. Their impact on BTS is astronomical!
Without them and the others mentioned then BTS would basically be a CD without a CD player.