This was on purpose - as it makes sense to me that every duplicated course (not yet published) is set to public when duplicated. Issues also arise when `website_sale_slides` is also installed, and `payment` is also an option, since by duplicating it would require duplicating the product (course) being sold.    I could also add `if 'enroll' not in default` and overwrite `copy_data` in `website_sale_slides` if you feel like this field should also be copied.