Mail.send API permission

Question

I have a doubt. Granting mail.Send (application) permission to the application object or managed identity (service principal), does it matter anymore. If I directly create a App RBAC policy and restrict the application object or managed identity (Service principal) to a mailbox, The restriction works perfectly even if I remove the mail.send permission from App object/service principal. So whats the need for mail.send? I may be wrong. Please let me know if today mail.send is even required to be assigned on app object or service principal if we need to restrict a mailbox or shared mailbox?

Answer 1

You don't need it, if you are already leveraging Exchange's RBAC for applications. It was needed with previous implementations, such as application access policies.