Does HDFS enforce authorization checks when dfs.permissions.enabled is false on a Kerberized cluster?

We are evaluating a multi-tenant HDFS deployment where Kerberos authentication is required for all client connections, but the cluster administrator is considering setting dfs.permissions.enabled to false to simplify namespace management. The concern is whether disabling the POSIX-style permission model removes all authorization barriers, effectively allowing any authenticated principal to read or write any path, or whether other controls such as ACLs or block-level tokens still constrain access. This behavior may vary by Hadoop release and by whether the NameNode treats the setting as a global toggle for the permission checker.

Can the HDFS NameNode still enforce Access Control Lists or other authorization rules when dfs.permissions.enabled is false, or does the setting bypass the permission checker entirely? What is the documented interaction between Kerberos-authenticated principals and HDFS authorization when the permission model is disabled? Does the DataNode block token mechanism provide any independent authorization protection in this configuration, or is it strictly an authentication and data integrity control?