Only if you disable iCloud photos completely. So no, you cannot turn off the feature unless you stop using iCloud photos.
I don't think they have been doing server-side scanning until now, hence the publicity. Do you have any evidence that shows they've been doing this before?
I wasn’t able to find the whole video though.
No time to watch, but. https://www.ces.tech/Videos/2020/Chief-Privacy-Officer-Round...
> Currently, although Apple holds the keys to view Photos stored in iCloud Photos, it does not scan these images
It also seems weird that the EFF wouldn't have complained about this before if Apple was known to be doing server-side scanning for some time now.
I also am not going to watch through an hour video, but I scanned the transcript and I didn't see anything that said that Apple currently (at that time) scanned content.