I suppose it could be confusing but it’s one of those cases where the API is built around the most utility and not necessarily around the easiest use. In your case you’ll want to look into the function ContainerPtrToValuePtr. That’ll give you the address.
void *ValueAddress = Property->ContainerPtrToValuePtr< void >( this );
UObject* PropertyValue = Property->GetObjectPropertyValue( ValueAddress );
I don’t see a version that does all that in one go, probably because the first call is part of the lower level property system and Get is part of FObjectProperty.