How can a user create an entry that is only enabled for 1 locale?

I would like a German user to only be able to publish an entry in the de locale.

I have set the permissions for the user to only publish in the de locale, but, when this user saves a new entry, the locale is then enabled for every locale.

I have tried disabling each locale in the channel settings, but, then the user is required to enable it for their own locale when publishing.

Similar question here, but no answer yet.