Everything in existence has a moment when it disappears. Even the multiverse we live in will one day face death.
Bai Ming transmigrated, and soon after, the consciousness of the multiverse chose him to be the protagonist of this great tribulation of ascension. The multiverse intended to support Bai Ming and help him survive the calamity.
If the multiverse failed to overcome the tribulation, it would have no chance to try again. Starting with the will of the multiverse, the entire world would be twisted into monsters, becoming a paradise for monsters.