Google scans photos you upload to google photos.
Apple scans photos you upload to iCloud, right before they are uploaded (so the scanning occurs on-device), but only for photos that were going to be uploaded anyways.
It’s the same outcome at the end of the day, even if the implementation differs.
I think the more vital question is - why is Apple choosing to go about this in such a controversial manner, when other companies have been doing it for years without people batting an eyelid? What’s wrong with simply scanning iCloud content and calling it a day?
Even the revelation that facebook had an army of employees manually vet controversial images to the point where many of them suffered mental breakdowns largely went under the radar because again, it’s a given that whatever you put on the internet is no longer private and well, it’s a problem that affected them, not us.
One possibility is that this is the first in a number of steps towards offering encrypted iCloud storage, and they can at least tell law enforcement that they are fairly confident that there is no child pornography on their users’ iCloud storage accounts (because there would otherwise be no real way of telling).
Granted, the most disconcerting part is the lack of control on the user’s part and how this largely comes down to “trust us to not abuse this in the future”. But there’s still a few months before this become reality, so expect more information and context to surface, and keep an open mind.