Even the “end to end encryption” option for iCloud (off by default, mind you) keeps the raw hashes of the unencrypted file content non-e2ee so Apple/USG can see

Even the “end to end encryption” option for iCloud (off by default, mind you) keeps the raw hashes of the unencrypted file content non-e2ee so Apple/USG can see who has which unique files and to where they spread.