The mess Huang An created on Tzuyu does not have to be told again.
It put Tzuyu, who was 16, at the world stage. Her story was covered by all major media in the world, and she was briefly a world figure.
However, JYP failed to exploit this opportunity.
Apparently he thought more about the prospects of Got7's Jackson in China, and failed to make Tzuyu a worldwide star.
Perhaps he was afraid of the return of another Suzy, who became bigger than the group.
Whatever he thought, he did not do anything to promote Tzuyu further.
The whole Huang An mess briefly brought a sense of patriotism to Korea, and GFriend, which will be remembered through the falling video in history, just happened to be promoting at that time.
It helped that GFriend had no foreign members.
So, GFriend briefly climbed the top position of Kpop, which it held until Apr 2016 when Cheer Up showed up.
Without the Huang An mess, Cheer Up, which is kind of a graduation song, would have shown up with Tzuyu at the center and it would have ended the tale of GFriend at that point.
Instead Gfriend actually fought with a slight edge, and forced this
Although the weaker showing of Navillera, complete with its eventual defeat on the hands of Wonder Girls, ended GFriend's heyday, being checked by an act, which, I have to say in retrospect, was not at a par with it hurt Twice' image.
Instead of seen as dominant over everyone else, Twice always had to exist with IOI, Mamamoo, BlackPink, RedVelvet and GFriend (and later izone and OhMyGirl).
Plus, the inability to use Tzuyu led to the 'all-fan' ethos, which hurt all girl groups btw. There was no clear star in Twice as the all fan ethos which crept up after the Huang An fiasco plagued all of KPop.
Now, since you know who is writing this , you probably guessed who was the ultimate beneficiary of all.
Because the 3rd Gen GGs did not show a single big star, like Yoona or Taeyeon or Tiffany Young, to climb to the top, that role was fulfilled by a Senior Singer, who managed to snatch the #1 idol position in 2017 on her 10th year!
If JYP had promoted Tzuyu despite of the Huang An mess, it is likely that some of the endorsement IU is doing (she is paid up to $1mil for each of them) would be Tzuyu's or someone else's.
But, because of the strange way JYP dealt with the Huang An mess, the all fan ethos robbed members of Third Generation Girl Group members the chance to become the next it girl, so a Second Generation figure (Lee Jieun) continues to reign even now.
to this day she sells out 1k+ dollar worth stuff like it's 
