I'm submitting this idea on behalf of Vodafone.
"Do not retain guest user email addresses in the backend. Compliance with data privacy regulations, such as the German Basic Data Protection Regulation (DSGVO), mandates the regular deletion of these data sets if they remain inactive for more than 6 months. Consequently, the customer is making a request for us to refrain from storing and displaying the existing email addresses in suggestions for guest users."
Regards,
Kirithika