While I tend to agree with you, the International Committee of the Red Cross does not:
Honestly, things are so different now from when the convention was written that it probably needs to be revisited. In '49 pictures would have been distributed by the warring parties through newspapers, now a random citizen with a phone can share them to the world on Twitter. Whatever your view on where the line sits regarding photos I would think we can all surely agree that there's a world of difference between sharing a photo of a PoW phoning their mum and drinking tea and bombing civilian targets.
Yeah i'd definitely agree with that.
It's likely the convention was written to prevent POW's being shown tortured / abused, which could then be displayed publically to their families.