connecting signal of aliased property in QML to C++ slot doesn't work

#include <QGuiApplication>
#include <QMetaObject>
#include <QQmlApplicationEngine>

class Handler : public QObject {
    Q_OBJECT
public slots:
    void handle()
    {
        qDebug() << "received";
    }
};

auto findMetaMethod(QObject *object, const char *signature) -> QMetaMethod
{
    const auto mo = object->metaObject();
    return mo->method(mo->indexOfMethod(signature));
}

int main(int argc, char *argv[])
{
    QGuiApplication app(argc, argv);
    QQmlApplicationEngine engine;
    engine.loadData(R"(
import QtQuick

Window {
    width: 200; height: 200; visible: true
    property alias value: mouse.value
    MouseArea {
        id: mouse
        anchors.fill: parent
        property bool value: false
        onClicked: {
            value = !value
        }
        Text {
            anchors.centerIn: parent
            text: mouse.value
        }
    }
    // onValueChanged: {} // existence of QML handler makes the C++ connection work
}
)");
    const auto sender = engine.rootObjects().constFirst();
    const auto signal = findMetaMethod(sender, "valueChanged()");
    Handler handler;
    const auto slot = findMetaMethod(&handler, "handle()");
    qDebug() << "signal" << signal.isValid();
    qDebug() << "slot" << slot.isValid();
    qDebug() << "connect" << !!QObject::connect(sender, signal, &handler, slot);

    return app.exec();
}

#include "main.moc"