Citation from the Oracle documentation:
A restricted use license to use Oracle Cloud File System is included with all editions of the database specifically for storing Oracle Database-related configuration files, including Oracle Database software binaries and homes, Oracle Database software administrative files, and Oracle Database software diagnostic files. Customers wishing to store their own data files, or non-Oracle Database software files including data files, binaries, administrative files, and diagnostic files, in Oracle Cloud File System must separately license Oracle Cloud File System.
This means "Extra charging for “user data” files like RMAN backups, exports and other database related files just makes life more difficult for clients that have committed to running their business on Oracle Clusters."
Oracle Cloud File System Licensing Requirements. This MOS 1322405.1 try to be an attempt to clarify the situation on Oracle CloudFS (0ACFS) Oracle Licence.