It still needs to conform to Revit’s tolerances.
We try to bring any geometry as native Revit geometry, if it fails we try and clean it up a bit, if that fails we try to import via the mesh. This looks like one of the fallback imports.
A quick test is to create a new file and add geometry direct shape and look at the error report, problematic areas are highlighted in Orange in the GH preview of the brep.
