Why is the previous weird you wonder, well, spirit beasts and cultivators might both use spirit energy but they are not the same, among the numerous differences there is one that has always caused conflict between human cultivators and spirit beasts that had gained human form and become cultivators as well.
That is the fact that unlike humans who have to form their dantian an then go through the awakening ceremony, spirit beasts have beast cores which they use as their dantian by innate in their bodies since birth.
