Let's not talk about other things, the Golden Core Dao within their Taoist School is precisely this way—each transition of the Golden Core is equivalent to a growth of a Realm. However, for each strong individual following the Golden Core Dao, their path is unique, and every refinement and advancement of the Golden Core is far beyond a mere layer of the True Immortal Heaven.
As the Zhu Jiuyin Ancestor Witch returned from ancient times as a God-Devil, the path he walks is definitely not the Path of the True Immortal, or perhaps the Path of the True Immortal is just a part of it. His level cannot be simply divided by realms.
It appears to be the True Immortal Sixth Heaven realm, but that is just the level he shows. With no one competing with him for authority in the Time Dao, it is believable if he can demonstrate battle power at the level of a Taoist Monarch.
