[AbilitySystem] Bind delegate to WaitTargetData

I am learning AbilitySystem, which is as powerful as it is confusing and undocumented, and I wanted to have a persistent GameplayAbilityTargetActor which broadcasts a delegate at regular intervals during it’s lifetime, that would later bind in a blueprint to attach some gameplay functionality to. Unfortunately I cannot enable the delegate pin in Wait Target Data node. How can I implement this use-case? Is there a better pattern?

Code:

DECLARE_DYNAMIC_MULTICAST_DELEGATE_OneParam(FSelectedTargetsDelegate, const TArray<TSoftObjectPtr<AActor>>&, selectedTargets);
    
UPROPERTY(BlueprintReadWrite, BlueprintAssignable, EditInstanceOnly, Meta = (ExposeOnSpawn), Category = "SelectAroundPawn")
    		FSelectedTargetsDelegate SelectedTargetsDelegate;

Blueprint:

Note how the Radius pin is visible but not the delegate. I also tried to do this via Construct Object from Class, but got a different error:

If I set ExposeOnSpawn = true explicitly, then compiler complains that the property cannot be exposed.

Really nobody knows? Should I ask on forums? I thought this was a fairly standard pattern - since there’s no other way to communicate with the rest of the game logic from the target actor.