You have configured the Feedback powerup and added a survey to a signature that has client-side rules enabled. When a response is left, the Email field displays 'Anon'.
For the survey responses to show the email address, the URLs used in the survey need to be populated with the recipient's email address when sending the email containing the feedback survey. When client-side signatures are deployed to the mail client, the recipient is not yet known, and, by default, the signatures will not be updated to include the recipient's email addresses in the survey URLs.
To ensure that recipient email addresses are filled in the survey URLs, you'll need to enable the Use recipient features Client-Side setting. For more information, see Apply Recipient Settings Client-Side.
When the Use recipient features Client-Side setting is enabled, the survey URL will automatically be updated by the Outlook Add-in to include the email recipient after the recipient is entered in the To field when composing the email.
Then, when the recipient clicks on one of the options in the survey, their email address is included in the response.