Missing option to delete guest note

There should be an option to delete a guest note.
Currently it is possible to go back to any version and the user has no way of deleting this.
Imagine somebody accidentally postet personal/sensitive information and already sent the link to his work group. Currently there's nothing he can do.
As far as I know in the EU the users have a right to delete personal data. If the personal data is in the document there has to be an option to permanently remove this data.