Geofencing is part of the criteria, but a car that can only drive in the USA but can’t drive in Europe still qualifies as level 5.

Similarly a car that refuses to drive in a blizzard but can do everything else is level 5. Being able to drive at night or moderate rain is mandatory however.

That said, there is plenty of slightly different definitions thrown about. I am sure someone is going to argue a car needs to be able to drive in any country to qualify etc etc.

Edit: To be clear existing self driving taxi services aren’t level 5 services with existing restrictions, but the car is physically capable of much more than it’s being used for. It can operate at night and in the rain etc they are however being extremely cautious.