...looks like a hallmark card...
Hallmark buys images just like this because their target audience likes them.
Checking the histogram...
Seriously? Checking the histogram? That's part of art appreciation?
...It provides a romanticized view of the world that allows one to escape the day to day troubles that we actually face.
It's emotive. It takes people to places they either once were or wish they could be, at least for a moment. It evokes a quiet, contemplative feel... something that is often sadly absent from our 36 megapixel, hyper-sharpened, cell tower connected, commuter world.
It's meant as art. It isn't realism. It wasn't intended to be illustrative, it was intended to be emotive and clinical technical perfection isn't required for that. Trying to find "technical perfection" in pictorialsm (or pointellism, or impressionism, or even cubism in painting) entirely misses the point of the work, which is to convey a
feeling of time and place rather than capturing an
image of a time or a place. I suppose you could even argue that each of those is a separate discipline with its own set of "rules" for "technical perfection" that are very different from other genres, and it's pointless to judge each of them by the other's set of rules.
ON EDIT... one more thought... The style of presentation of this image works because of the subject and intent of the image. In the more pragmatic world of photo-illustration, advertising, product illustration and so forth the techniques used here would likely render an image unusable. Context is everything when we're consumers of imaging, and sometimes it's difficult to place an image in its proper context when we view it.