The target based approach of qt6_add_resources automatically does qt quick / qml file processing.
This doesn't happen with the old non-target based qt5(6)_add_resources function, as well as AUTORCC.
We should document this behaviour, and perhaps discourage the use of AUTORCC going forward.
Resulted from CMake public API discussion at https://codereview.qt-project.org/c/qt/qtbase/+/317353/1/src/corelib/Qt6CoreMacros.cmake#309
From the same comment, there was also discussion about discouraging usage of qrc files with CMake, and recommend using the target based qt6_add_resource approach.