The appearance of Taibai Jinxing must have been permitted by the Celestial Emperor Taiyi. It had to be said that Taiyi certainly knew how to pick his moment!
The current actions of the Human race amounted to an act of self-annihilation.
Initially, Taiyi had listened to Baize's advice and intended to spare a million male humans—which wouldn't have been total annihilation, though the race would have eventually faded away.
Chapter 503