I expect in the near future all digital cameras to digitally sign the images they take. Even before AI slop, it was useful to avoid manual alterations. AI makes it all too easy, so it makes sense.
However, this will certify only the original image. I think the missing part of this is additional layers of certification which allow some image editing (e.g., rotating, contrast, etc.) yet clearly document that the image was modified and link to the original image ID. Kind of like a signed git log.
People may be interested in the work of the Coalition for Content Provenance and Authenticity (C2PA) https://c2pa.org/
if such a method gains traction then so will the effort to bypass it. either by stealing private keys or just projecting light onto the sensor.
There will always be a way around it. There are even open-source alternative/hacked firmwares for professional DSLR cameras where tampering with the signing may be possible.
And this still doesn't help any other kind of image e.g. screenshots, photo of a screen etc. that can make the camera signatures largely pointless depending on the context.
EXIF data is stripped for a good reason - because it can be a privacy hazard. Suddenly this plays no role anymore?