Which idol group truly paved the way for K-pop in the West?

Article: "Why is there a lot of noise on who paved the way for K-pop in the U.S market?"

Source: Pann

Paving the way means having huge success overseas, pioneering the country's music market and laying the foundation for K-pop (ex. BOA - East/Japan etc.) For U.S and Europe it's clearly BTS. 

Has there been anyone that can rival BTS' impact on K-pop in the West? Psy's 'Gangnam Style' was a one-hit wonder that only became a trend because of the choreo "horse dance." 

So why does everyone keep putting down BTS' achievements? All I see are people saying their seniors paved the way ㅋㅋㅋ. I hope people realize how hard ARMY in America worked to get BTS on radio and that was the reason for BTS' successㅠ.

1. [+453, -122] If their seniors truly paved the way wouldn't EXO BIG BANG have been the first to attend Billboard Music Awards before BTSㅠㅠㅋㅋㅋㅋㅋㅋㅋㅋㅋㅋ ? 
2. [+423, -27] I'm curious about this too. How exactly did the previous generation of idols, their seniors, pave the wayㅋㅋㅋ?
3. [+420, -29] It's not just 1 or 2 idol groups that knocked on America's door, its just that one group was successful in the end. No SEA singers have been able to successfully enter Korea either but if one of them breaks through doesn't it mean all the groups that came before them paved the way?
4. [+93, -16] Aren't most of them Big Bang fans?? Big Bang was the first Korean act to rank on Billboard paving the way for BTS to succeed. Without Big Bang there would be no BTSㅋㅋㅋㅋㅋㅋㅋㅋㅋ
5. [+77, -3] Overseas fans and a handful of Korean fans sent handwritten letters, bouquets, and gifts to DJs so that they can spin, promote and air BTS on radio. American ARMYs really put in a lot of effort and worked hard as a team to get them on Spotify, Radio, Muse. Isn't this what pioneering is? Even though the previous generation of idols went there first the results were different. BTS didn't gain their foothold through nothing. ARMY worked really hard. 
6. [+55, -105] I hope ARMY can recall the days their faves were just nugu centipedes rolling around in dirt before they hit it big ㅋㅋ
7. [+54, -0] BTS achieved what they have now not by following the paths of their seniors or riding the Korean Wave but through pioneering their own way. 
8. [+43, -6] This is what Big Bang fans have always been saying. If you want to see ARMYs come out in the comments just mention their faves breaking into the U.S market and they suddenly attack you with the group's music achievementsㅋㅋㅋ Do they think their faves are at GD's levelㅋ ㅋ ㅋ  ㅋ ㅋ ㅋ ?