I've put together a somewhat simple app to demonstrate drag and drop using .draggable and .dropDestination. I'm using a simple custom object with two strings and two enums as properties. I have followed all the steps for UTType and implementing Transferrable. I have two views displayed from the ContentView. The left side is a List with four of my custom objects (a user). The user is a "card" I implemented in a separate imbedded view. The right side is a drop area which is a ZStack with a List inside which displays an array of users dropped onto the ZStack.
The draggable seems to be working fine. I can drag a user "card" around. The drop doesn't work. I have the .dropDestination on the ZStack and the initial closure on the .dropDestination doesn't seem to fire. I placed a print() in both closures and the print() in the first closure never prints. The "isTargeted:" closure does fire (a little unreliably) on the iPhone simulator and (less reliably) on the iPad.