AWS IAM vs Key Vault Access Policy

Manage IAM users and their access - You can create users in IAM, assign them individual security credentials (i.e., access keys, passwords, and Multi-Factor Authentication devices) or request temporary security credentials to provide users access to AWS services and resources.;Manage IAM roles and their permissions - You can create roles in IAM, and manage permissions to control which operations can be performed by the entity, or AWS service, that assumes the role. You can also define which entity is allowed to assume the role.;Manage federated users and their permissions - You can enable identity federation to allow existing identities (e.g. users) from your corporate directory or from a 3rd party such as Login with Amazon, Facebook, and Google to access the AWS Management Console, to call AWS APIs, and to access resources, without the need to create an IAM user for each identity.