Another option would be to disable the creating of a guest user with the specified domain. Capturing may still happen, but the captured email would never actually be saved.
We and our partners process your personal data (such as browsing data, IP Addresses, cookie information, and other unique identifiers) based on your consent and/or our legitimate interest to optimize our website, marketing activities, and your user experience.
Another option would be to disable the creating of a guest user with the specified domain. Capturing may still happen, but the captured email would never actually be saved.