Disagree, this is a great feature. It's not a good feature on it's own, but with identified senders etc it's a big improvement. Identifying senders is the big piece in this campaign, the unsubscribe requirement is icing. If they continue to send emails after you unsubscribe, they get spam binned. The basic idea is to stop people from sending from unidentified servers then improve their etiquette. It's certainly not perfect but this is a very positive step. It's certainly not the end of the war either.
BTW I think you should be using Gmail's unsubscribe link rather than the one in the email itself as that allows Google to track compliance.