You confused the 2 new features. The child pornography detector compares perceptual hashes. The iMessage filter tries to classify sexually explicit images.

Could you explain please - can these hash comparisons be extended to other areas such as contextual analysis of photos or texts?

For example would it be easy now to get to the hypothetical scenario where texts containing certain phrases will be flagged if some partner / regulator demands that?

Or doing face recognition on images, etc.? Or is this still completely different from that

oh that's actually kind of good news then. I couldn't believe Apple wouldn't know about the inadequacy of their PC