Windows hides some files by default to:

Hiding system files by default protects the integrity of the operating system by making it less likely for users to inadvertently corrupt or delete files crucial for Windows operations, preventing system instability or failure.

Protecting confidentiality is typically achieved through security permissions and encryption, not merely by hiding files, as hidden files can still be accessed and viewed by changing folder options.

Hiding files makes them less accessible, not more, so this option contradicts the purpose of improving access.

Hiding files does not reduce their size or save disk space; it only changes their visibility within the file system.