They are talking about the payment for the email hosting service. Not talking about sending payments to others via email as your comment seems to be talking abo

They are talking about the payment for the email hosting service. Not talking about sending payments to others via email as your comment seems to be talking about. The idea being that if you want private email then you can’t pay for it with your Visa/MasterCard/AmEx/etc because if you pay for it that way then you tie your irl identity to the account.