The Autodesk DWG specifications set a limit of 32676 faces/vertices for polyface meshes in a DWG file. Currently, you won’t be able to open files containing polyface meshes beyond this threshold. We will address this issue with our fall 2023 release.
This issue typically arises with DWG files containing terrains with many faces. Try removing such meshes from your DWG file or exporting them as solids as a temporary workaround.