KDE_INSTALL_USE_QT_SYS_PATHS leads to nonsensical install paths

krita install its QML files to $SNAP/snap/kde-frameworks-5-96-qt-5-15-5-core20-sdk/3/usr/lib/x86_64-linux-gnu/qt5/qml.

Question: Are the other snaps also wrong? Has this ever worked? It seems that this wrong path is indeed correct, seeing that it uses Qt from the SDK at build time. Ideas:

• don't set KDE_INSTALL_USE_QT_SYS_PATHS, but figure out how to change the install path to include the Qt major version ("5"). This should require only moderate digging in CMake files.