Doh.
3D views would be extremely boring if they showed the aircraft size to scale, so they are displayed highly magnified.
Think about it - those position plots have to be at least half a second apart, probably more, which at 300kt would make those vertical lines a minimum of 250' apart, and those A320s at least 1000' long or more ...
Perhaps AirNav need to issue a health warning with RadarBox 3D :-)