I think you might be mixing up two features here. One is deleting a message from your own inbox (this part about your email example makes sense). The other is

I think you might be mixing up two features here. One is deleting a message from your own inbox (this part about your email example makes sense). The other is deleting a message that was sent to someone else from _their_ inbox. Which email does not allow you to do. Except some clever people tried to implement this (notably Outlook and/or Microsoft Exchange has such a feature IIRC) where it sends another email to "recall" the earlier message. It's funny when you receive those recall messages in a non-Microsoft email client and on a different server than the Exchange sever they're using. I.e. you just ignore their request to recall and now you _really_ go read the message they're trying to recall, because it makes it _more_ interesting. Also googling this quickly it seems even if you stay completely within the Microsoft ecosystem it only works if the recipients didn't open the original email yet: With message recall, a message that you sent is retrieved from the mailboxes of the recipients who haven’t yet opened it. https://support.microsoft.com/en-us/office/recall-or-replace-an-email-message-that-you-sent-35027f88-d655-4554-b4f8-6c0729a723a0 https://support.microsoft.com/en-us/office/recall-or-replace...