I wonder if the place where the Monster Beasts from the Lower Realm ascend to is the territory of the Demon Tribe in the Spirit Profound Realm. Most of these Monster Beasts do not harbor significant hatred towards humans; perhaps they are compelled to submit to the tyranny of the Demon Tribe's Capabilities and turn to attack Human Cultivators.
Just like White Painting, it was the Spirit Beast of the Dan Immortal Master; how could it possibly become an enemy of humans unless coerced or brainwashed? It has been over three hundred years since White Painting ascended; I don't know what the situation is now.
The information provided in the Jade Slip of the Flying Spirit Hall is too scant, all of it vague and simplistic, probably just enough to give the Ascenders a rough idea of the Spirit Profound Realm. For more specific information, one has to inquire on their own.