In Revit Connector version 2.23, elements were exported considering “category”, “BuiltInCategory”, and “SpeckleType” with specific info about the element, in this case a “Level” object.
For the specific case of Levels (which you correctly identified as stripped to “just” Collection) this is the one category we are still looking at. Is your question / workflow predominantly with focus on level information? All of the other objects are as before.