With the "Attribute with replacement value" storage rule, the replacement value is displayed as a "placeholder" in an input field if no explicit value is stored. However, this only works if input fields are also available. If the field is displayed as immutable, no value is displayed.

You can test this by configuring the visibility in the editor for the attribute with replacement value to "read only". If you create a new object or edit an existing one in a grid or a table with attachment/edit dialog, no value is displayed if no value is explicitly stored.