Why is the performance consumption of Movable models so high in Unreal

I am trying to load resources from pak at runtime and achieve simultaneous loading and display, but I found that if I want to change the parent object of the generated model during runtime loading, I must set it to Movable. However, this would incur significant performance overhead. Can Unreal set the object to static after the resource loading is completed and the structure is no longer modified to reduce performance overhead.