What would be the expected behavior for an NSP?

Your expectation is broadly correct: resources in the same Network Security Perimeter profile should have mutual network access, but NSP does not replace data-plane authentication. Implicit member-to-member access is designed for managed identities and role assignments; account keys, SAS tokens, or non-onboarded services can still require rules. For BULK INSERT, configure a managed identity for the Azure SQL logical server, grant it Storage Blob Data Contributor on the container or account, and use a database-scoped credential with managed identity rather than a storage key. Confirm SQL Database and storage are associated with the same profile and mode, then inspect NSP diagnostic logs for denied flows. Azure SQL’s NSP integration remains documented as preview. If the managed-identity path still requires public-IP and FQDN exceptions, keep them during testing, capture denied-flow records, and open Azure support; that would indicate a preview limitation or defect, not intended same-perimeter behavior.