Use case:
As an example, let's say we have 3 follow up emails when a customer buys our product.
  1. after purchase
  2. asking if the customer has received the product
  3. asking for a review.
After the second email some customers are complaining about the product and in this case, it would be great if we could remove them so they don't receive the 3rd email where we ask for a review.
Arguably the best way to achieve this would be to add a field where we could enter their order ID into a blacklist either for this 3rd email sequence or forever.