Their privacy policy very strongly suggests that they are the data processor only when the account owner (Publisher) provides the email address, which they call indirect subscription.

Direct subscribers are users who subscribed themselves via the Revue service. and the privacy policy says nothing about providing direct subscribers' private data to the Publisher.

Their closure announcement does not distinguish between the types of subscriber.

So either the Publisher is only getting the indirect subscribers' info (and isn't being told they are losing the direct subscribers) or the Publisher is getting direct subscriber info which the direct subscriber never agreed to allowing (unless that is a separate agreement from the privacy policy, in which case presumably some permission was indeed obtained).