In Unreal 5.1 Datalayer behaviour has changed. Now we no longer need to unload layers. Before if you loaded a layer it would load the complete asset but just leave it hidden. Now if you load the datalayer it appears to just load the meta data for the actors on the layer. Once the layer is Active now textures are streamed it (assuming meshes too). This makes for smoother transitions in RunTime datalayers.
See example code below.
https://dev.epicgames.com/community/s...