Qt.CheckStateRole not displayed in QAbstractItemView

A Qt.ItemIsUserCheckable cell in a QAbstractItemView (seen in QTreeView and QTableView) is not displaying the Qt.CheckStateRole. The checkbox is always displayed as unchecked. The problem is not present in 6.2.3, but is present in 6.2.4 and 6.3.0.

There is a semi-minimal example in the .py file attached. In the example the 0th row Enabled value should be checked and the 1st row should be unchecked. The checkboxes should be properly user checkable.