Unable to delete archived data chain objects. The delete option is greyed out.

Hi,
We are trying to delete archived data chain objects i.e. Node types, Hierarchy sets and Node sets.
But the delete option when we inspect the object is greyed out.
There are no viewpoints associated with those objects.

We checked the following oracle document:

It says that we can only delete application.
But if that really is the case, then why is there a delete option given for the data chain objects?
Is there any process we need to follow to delete the objects.

Another consideration: we are using custom node properties to track the creator and last editor of the node.