The List-Unsubscribe header will improve email deliverability as ISPs like Gmail and Outlook will recognize it as an email best practice
In Gmail, if you are a good sender, this will appear in your emails.
If a subscriber clicks this link, it will send an email to you indicating that this person wishes to be removed from the list. For now, you must manually unsubscribe these contacts as there is no automatic way for it to happen, we are working on a better, automatic solution.
