It's a nothingburger if all they're doing is just backing up WhatsApp user data. It's not if the terms of the agreement allowed for anything else, which we don't really know because that part of the complaint has been redacted.
it's not nothing if most whatsapp groups contain at least one member that gives an un-ecrypted archive to google. sure it's stated in the fine print, but nontheless most ppl argue that whatsapp is "private because encryption right?"