setting property value 'ScaleToPages' at a spreadsheet with no effect?

Hello,
when I set the property 'ScaleToPages' to 1, I get still '0' returned.
The output on the cmd-line is:

default ScaleToPages = 0
changed ScaleToPages = 0

I would expect:

default ScaleToPages = 0
changed ScaleToPages = 1

My code reads first the default value of ScaleToPages', sets it to 1 and
re-reads its value:

    Reference< XSpreadsheetDocument > xSpreadsheetDoc ...
    Reference< XStyleFamiliesSupplier > xFamiliesSupplier{ xSpreadsheetDoc,
UN
O_QUERY_THROW };
    Reference< XStyleLoader2 > xTargetStyleLoader{
xFamiliesSupplier->getStyle
Families(), UNO_QUERY_THROW };
    Sequence< PropertyValue > aOptions =
xTargetStyleLoader->getStyleLoaderOpt
ions();
    xTargetStyleLoader->loadStylesFromDocument( xComponent, aOptions);
    Reference< XNameAccess > xFamilies{
xFamiliesSupplier->getStyleFamilies(),
UNO_QUERY_THROW };
    Reference< XNameContainer > xFamily{
xFamilies->getByName("PageStyles"), U
NO_QUERY_THROW };
    Reference< XStyle > xStyle{ xFamily->getByName("Default"),
UNO_QUERY_THROW
};
    Reference< XPropertySet > xStyleProps{ xStyle, UNO_QUERY_THROW };

    OUString propName = "ScaleToPages";
    sal_Int32 x = -1;
    assert( xStyleProps->getPropertyValue( propName) >>= x);
    std::cout << "default ScaleToPages = " << x << std::endl;
    x = 1;
    Any X;
    X <<= x;
    xStyleProps->setPropertyValue( propName, X);
    x = -1;
    assert( xStyleProps->getPropertyValue( propName) >>= x);
    std::cout << "changed ScaleToPages = " << x << std::endl;

What I'm missing?

best regards,
Oliver