It is only because the time has been short and the ruling foundation of the Datong Society is not yet deep enough throughout the entire Xuanyang Realm. Otherwise, he would turn the Xuanyang Sect into a department under the rule of the Datong Society in a split second.
Nominally, nothing has changed, but practically, things are already vastly different.
For instance, the Xuanyang Sect no longer recruits disciples from the outside, and all already admitted disciples no longer stay within the Xuanyang Sect's mountain gate, but are instead dispatched to various regions to truly fulfill the mission of serving the people.
Chapter 321