You have not linked to a support page, you have linked to a PDF titled 'Legal Process Guidelines'. (That is definitely NOT a privacy policy.)

https://support.apple.com/en-us/HT202303 would probably be the right support page, however, Apple mentions what is done – and not what is NOT done, in particular end-to-end-encryption of iCloud backups.

I still agree that Apple plays in a different league than Facebook with regard to privacy. At the same time, there is still a lot to do for Apple, especially regarding data security. Just a current example:

https://www.mac4n6.com/blog/2018/3/30/omg-seriously-apfs-enc...