When adding a Quick Control with the design view, the import of QtQuick.Controls is versioned

I created the usual barebones project as a Qt Quick Application, so it contains nothing but a Window in its QML, and added a Button with the Quick Designer. It added an import QtQuick.Controls 5.15. Running that on Android failed, due to a complaint that that particular version isn't installed.

I thought the current way to do imports is without a version? I removed the version number from the import, and the app ran correctly on Android.