These three visitors from the Upper Realm, more accurately, can no longer be considered as such; referring to them as coming from the outer realms is more appropriate.
With more people arriving, there's a mix of fish and dragons, some pretending to be something they're not. In a big forest, every kind of bird exists, and in the vast universe, every kind of Daoist exists.
The true Upper Realms refer to those boundary domains that had planted the seeds of inheritance on the Jinxiu Continent long ago, even before the new Epoch. These were actions taken by powerful harmonized immortals in the boundary domains, who foresaw something at the start of the new Epoch and thus arranged for their own Daoist sects to be established in advance.