I think it's very likely the next iPhone will have some form of authenticity proof too, I just hope Apple doesn't go with its own standard again that's incompatible with everything else.
Samsung were also the ones who demonstrated a fatal flaw in C2PA: device manufacturers are explicitly trusted in implementation.
C2PA requires trust that manufacturers would not be materially modifying the scene using convolutional neural networks to detect objects and add/remove details[1]
I think it's very likely the next iPhone will have some form of authenticity proof too, I just hope Apple doesn't go with its own standard again that's incompatible with everything else.