The thing is that while many companies have access to your data in various services, Apple has designed their systems such that they can’t access most user data. Can’t be both ways, your data is either private or not, and many would prefer it stay private.

As I understand the actual situation with iCloud and CSAM scanning is Apple does scan iCloud photos (the ones that users choose to upload to iCloud) if they can. A few years ago they tried to design a privacy focused version of that scanning that would allow them to access that kind of content for the purposes of reporting it, while preserving the users privacy. It was supposed to happen on device(while most companies only scan the photos on their servers) before the photos were uploaded, and use hashes to compare user photos to known CSAM material. This seemed an odd thing at the time, but a while after that Apple released end to end encryption for iCloud Photos, which means they can’t scan the uploaded photos anymore because they don’t have that access. Some have a theory that the big tech companies have regular contact with various government/law enforcement/etc. agencies and the on device scanning was a negotiated by them as a response to Apple’s plans to add E2E encryption to iCloud Photos, among other previously less secure services.