I think it's IBF's fault to tarnish the world championship by granting the association rights to select tournaments qualifiers. According to the performance, China should disqualify Wang Yihan, but Wang is the current top ranked player. So the so called World championship is tarnished because it's a tournament without the best player, even the 1st ranked player.
But China still sent Wang Yihan, the worst WS in the super league. this actually saved IBF's face. China could send others by regulations, that would make the world championship without top ranked players. But instead of doing that, China sent the top ranked, but not the best player, therefore made the world championship a tournament without the best player in the world.
What a joke! Nowadays, we just simply cannot find a tournament which can truly determine who is the best in the world.