How to Block Ad-Hoc Email-Based Subscriptions

The old Set-MsolCompanySettings cmdlet is no more, so how can a Microsoft 365 tenant block email-based subscriptions? With the Graph, of course! Seriously, there’s no 1-to-1 mapping from the old cmdlet to a new, but some of the settings are available in the Entra ID authorization policy. We can update the authorization policy with PowerShell to block email-based subscriptions, like Copilot Studio.