I think the article got that wrong. Apple does manually review tagged images, but does not access the original image, but the security voucher containing metadata, including the NeuralHash and a "visual derivative" of it (see Apple's spec [1]).
Also, this only applies to pictures you upload to iCloud. So, it's not like they're accessing your personal photos without telling you.
Most iPhones have icloud backups enabled, which will trigger this detection automatically. Most iPhones are set up to upload every photo to icloud in case you lose your phone.
Also, this only applies to pictures you upload to iCloud. So, it's not like they're accessing your personal photos without telling you.
[1] https://www.apple.com/child-safety/pdf/CSAM_Detection_Techni...