MicrosoftConsidering that most GUI-based applications still don't support OAuth, and SMTP Basic Auth should be disabled on your tenant to prevent abuse, this feature isn't functional or useful for us. We still have to resort to using third party mail relay tools such as SendGrid to send legit emails because they allow us to use basic authentication while not exposing our Microsoft tenant to SMTP auth attacks.
HVE really should be in its own separate service offered by Microsoft entirely to protect your main Tenant. It doesn't fit well in Exchange Online.
