We all know how well AI works.
And the feature to make sure that all 'similar' or 'altered' images generate the same hash is bound to generate millions of false positives.
Or, the sensitivity will be wound back so far it will be useless.
Don't forget, the AI is not running on a giant bank of high-powered servers. It is running on your phone. Which, really, is not that high-powered.
How much power will this use, and how long will your battery charge last when it is scanning your photo library?
I cannot see this working well for Apple.