Hi @Lässig, Yvonne ,
As per my understanding, you added default content and columns as tag to the Document Set content type. So, when users create a document set, they fill in the tag column field and default content files are all tagged. But the users can delete the values of the tag column fields of the default files, right? Apologize in advance if I misunderstood.
From my point of view, this is by default if you set the tag column editable and the users have higher permission level than "Contribute".
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