Chi Yun Mountain was originally the gateway to the Cloud Top Fairy Palace.
At a certain historical moment, the Cloud Top Fairy Palace was reduced to ruins, and Chi Yun Mountain was consequently sealed off.
The Divine Fruit matures every thirty-three years, and in fact, it is the last foundation of the Cloud Top Fairy Palace. Only every thirty-three years can this bit of foundation be nurtured to support the reopening of Chi Yun Mountain and the search for an heir to the Cloud Top Fairy Palace.
In other words, although the Divine Fruit is indeed a rare treasure of the world, Chi Yun Mountain does not exist for the sake of the Divine Fruit. It is more about using the Divine Fruit as the power source of Chi Yun Mountain to support the effectiveness of various arrangements on the mountain.