Entity created from C++ has missing properties (as seen by JavaScript) wrt Entity created from QML

A cuboid entity is created from the following QML:

Entity {
id: cuboid0
components: [
CuboidMesh

{ xExtent: 1 yExtent: 1 zExtent: 1 }

,
Transform

{ translation.x: -1.5 }

,
PhongMaterial

{ diffuse: Qt.rgba(0.85, 0.85, 1, 1) }

,
ObjectPicker

{ onClicked: selectObject(cuboid0) }

]
}

Similarily, a cuboid entity is created from C++:

auto cuboidEntity = new Qt3DCore::QEntity(rootEntity_);
cuboidEntity->setObjectName("Cuboid");
auto mat = new Qt3DExtras::QPhongMaterial(cuboidEntity);
mat->setDiffuse(QColor(217, 217, 255));
auto t = new Qt3DCore::QTransform(cuboidEntity);
auto mesh = new Qt3DExtras::QCuboidMesh(cuboidEntity);
auto picker = new Qt3DRender::QObjectPicker(cuboidEntity);
connect(picker, &Qt3DRender::QObjectPicker::clicked, [=]

{ emit entityClicked(cuboidEntity); }

);
mesh->setXExtent(1);
mesh->setYExtent(1);
mesh->setZExtent(1);
cuboidEntity->addComponent(mat);
cuboidEntity->addComponent(t);
cuboidEntity->addComponent(mesh);
cuboidEntity->addComponent(picker);

Note: entityClicked signal is connected to selectObject, which does:

for(var x in e)
console.log("dump:", x, e[x])

The result for the entity created from QML is different from the output for the entity created from C++:

created from QML:

qml: dump: Qt3DCore::Quick::Quick3DEntity(0x7f9f5d637520)
qml: dump: objectName
qml: dump: parent Qt3DCore::Quick::Quick3DEntity(0x7f9f5d62dad0)
qml: dump: enabled true
qml: dump: defaultPropertyTrackingMode 0
qml: dump: propertyTrackingOverrides undefined
qml: dump: data [object Object]
qml: dump: childNodes [object Object]
qml: dump: components [object Object]
qml: dump: objectNameChanged function()

{ [native code] }
qml: dump: parentChanged function() { [native code] }

qml: dump: enabledChanged function()

{ [native code] }
qml: dump: defaultPropertyTrackingModeChanged function() { [native code] }

qml: dump: nodeDestroyed function()

{ [native code] }
qml: dump: setParent function() { [native code] }

qml: dump: setEnabled function()

{ [native code] }
qml: dump: setDefaultPropertyTrackingMode function() { [native code] }

qml: dump: propertyTrackingOverridesChanged function()

{ [native code] }
QQmlExpression: Expression qrc:/test.qml:44:13 depends on non-NOTIFYable properties:
Qt3DCore::Quick::Quick3DEntity::data
Qt3DCore::Quick::Quick3DEntity::data
Qt3DCore::Quick::Quick3DEntity::childNodes
Qt3DCore::Quick::Quick3DEntity::childNodes
Qt3DCore::Quick::Quick3DEntity::components
Qt3DCore::Quick::Quick3DEntity::components


created from C++

qml: dump: Qt3DCore::QEntity(0x7f9f5f7abb60, "Cuboid")
qml: dump: objectName Cuboid
qml: dump: parent Qt3DCore::Quick::Quick3DEntity(0x7f9f5d62dad0)
qml: dump: enabled true
qml: dump: defaultPropertyTrackingMode 0
qml: dump: objectNameChanged function() { [native code] }

qml: dump: parentChanged function()

{ [native code] }
qml: dump: enabledChanged function() { [native code] }

qml: dump: defaultPropertyTrackingModeChanged function()

{ [native code] }
qml: dump: nodeDestroyed function() { [native code] }

qml: dump: setParent function()

{ [native code] }
qml: dump: setEnabled function() { [native code] }

qml: dump: setDefaultPropertyTrackingMode function()

{ [native code] }

In particular, the entity created from C++ doesn't expose the 'data', 'childNodes', 'components' properties.

Also, possibly related, is the fact that we get this warning: "QQmlExpression: Expression qrc:/test.qml:44:13 depends on non-NOTIFYable properties" for the exact same 3 properties.

So it is not possible to inspect scene tree hierarchy and access aspect such as transform from JavaScript?

Which of the above is the intended behaviour and which is not?