You're right that the idea isn't a good fit for instances like the ones you described, but I think it certainly has applications. For one thing, you could potentially synthesize an image of a part of a city from a particular era taken from a point of view that no actual photograph was taken from. Instead, it's a synthesis of contemporary photos with inferences made from contemporary weather data, contemporary maps, potentially drawings, etc. It's an exciting idea.
I see no exciting uses of this technology for recreational purposes. You wouldn't be able to take a photograph of the Library of Alexandria because that existed before we started gathering the data. And taking synthesized photos of your trips would make no sense, why would you even take the picture at all in that case?
My point is that it's a bad article. Technology is cool though.