LIDAR (.las) to Rhino Model

Hi, would like to ask if anyone has experience converting LIDAR files (.las) to Rhino models. I’m looking a city model of around 10,000 buildings (massing models), ideally with some polygon simplifications so that the edges are not overly rough.

Have searched online and tried QGIS/ArcGIS but nothing seem to work well. Any suggestions/help would be great. Thanks!