It’s simple:
Since the AI does all the work more efficient than us humans, you don’t need to reorganize the apps, since it already has done so in the best way possible. Hence the term “smart” drawer. 🙃
In all seriousness, this has been criticized since the feature was released in OS 3.0. Smart Drawer unfortunately still is a “take it or leave it”-function: Either you accept and adapt how the AI sorted your apps or you completely disable it.