I don’t understand what you mean. The goal was to get rid of duplicates when there is more than one instance placed and oriented in the same way in the model, leaving just one. It doesn’t remove anything from inside the component/group (is that what you mean by “ingredients”?) and intentionally leaves behind one instance. Are you asking for a tool to delete all instances of a selected component/group, including the selected one and regardless of duplicate position and orientation?
This is possible. I’ll take a look. The main drawback is that if your model has a lot of components it may take a long time because the plugin will have to examine every instance of every component in the model.
Edit: Because instances may be nested in different parents, this is a lot more complicated than I thought at first. Unless there is a lot of demand, I’m not inclined to spend the effort it would take as this is a somewhat special tool to recover from a peculiar modeling situation anyway.