I can't remember the source so take this as you will, but WhatsApp are appealing such a large fine because the privacy policy was in the middle of being updated during a transition. The policy was correct after the fact and ever since.
If I renegade on a contract with my bank because I was moving house I would still be sued into bankruptcy. Multibillion dollar companies have the onus to keep their legal documents (terms of service, privacy policy) up to date.
