I think what got me worried is the GPs take that "I expect in the near future all digital cameras to digitally sign the images they take". Sure, if you have your special, verification-enhanced camera, go for it. But if this goes like with smartphones and we have all cameras embedding such a signature - and therefore all cameras are made locked-down and tamper-resistent - then we have another category of devices removed from control of their users.

> Any of us are still perfectly free to upload images for fun to forums or social media or whatever that are private, or edited or whatever we like.

First, the paper proposed a method of embedding the metadata inside the actual image pixels in a way that makes it difficult to remove. I think it's still possible, but you're will need a specialized tool to do so and it will alter the image.

Second, that's assuming forums or social media would still be allowing uploading unsigned images. If AI images really become as much of a problem as anticipated here, then sites might decide to block any image they can't verify completely.

> Like, can you give examples of specific cases you are imagining where simultaneously the photo itself reveals no information about time and location [i]and[/i] it's something local/national/international-newsworthy where people would fear AI-alteration?

All kinds of photos from warzones have this property. We wouldn't have an entire science of geolocating photos from landmarks that were accidentally captured if everyone was so easy with putting their GPS coordinates in the file.