A cloud-based identity and access management service for securing user authentication and resource access
From the horse's mouth (albeit a bit ambiguous): - This feature requires Microsoft Entra ID Governance or Microsoft Entra Suite subscriptions, for your organisation's users. Some capabilities, within this feature, may operate with a Microsoft Entra ID P2 subscription. For more information, see the articles on each capability for more details. To find the right license for your requirements, see Microsoft Entra ID Governance licensing fundamentals. Edit: - I finally found a definitive answer: "Access reviews are a Microsoft Entra ID Governance capability".