Yup, the only reason google is able to offer one click unsubscribe is because the people sending the message have enabled the list-unsubscribe header. They are

Yup, the only reason google is able to offer one click unsubscribe is because the people sending the message have enabled the list-unsubscribe header. They are intentionally making it easy to unsubscribe. No legitimate email marketer wants to send messages to someone who doesn't want them.