I found plenty of trivial examples how to use the different draggable directives but now I want to do this progmatically. There is a minimal sample app that demonstrates the problem. It receives the "dropped" event but the previousIndex and currentIndex are always the same.
https://stackblitz.com/edit/angular-8-drag-and-drop-dynamic-components
Click the add button a few times and then try to move them.
The issue is (was) a real bug: https://github.com/angular/components/issues/16961