I have the current hatchback version, and with the factory-supplied, swing-down parcel shelf installed and the lift gate closed, the area behind the rear seats is totally enclosed by rigid, opaque surfaces; it’s impossible to see any of the contents from inside or outside the vehicle.

I don’t know whether this area has the same legal status as a trunk, but practically speaking, it’s no more accessible to the driver than the trunk of a sedan having rear seats that could be unlatched and folded down by someone in the passenger compartment.