Service Desk 3.2 introduces a new Approvals feature. However, the approvers can only approve the ticket via the UI
Make it possible for Approvers to truly approve/decline requests via email
The prior ticket that resolved this request still requires access to the Service Desk server. A true email-based approval would be driven by the reply to the email itself. All the previous resolution did was add convenient "Approve" and "Deny" shortcuts to the portal, but they still required you to use the portal.
If an Approver is out of the office and the Service Desk is not accessible when not on the corporate network (I assume a fairly common scenario), you cannot Approve/Deny using the email that gets sent. Often, our Approvers just reply "Approved" to the message, thinking this is sufficient, but it just adds a comment of Approved, and does not log their Approval and transition the ticket.
A true email-based approval could use an automation to parse a carefully crafted mailto: link inserted in the Approval emails that get sent and thus rely only on the email to log approvals.