With all due respect, IMHO you are starting from an incorrect assumption that there is some pristine "real" images that can be produced from a scene. Between your Nature-begotten scene and your photograph was some technology. In a digital camera that technology consists of some pixels, some colored filters, a CPU and some algorithms all working on some analog data of simple brightness that tried to reproduce something close to what your eye/mind combination perceived. Two separate cameras shooting the same scene (side by side, with the same exposure, no post-processing, etc.) will likely give you two different saturation/contrast/color/etc. Which one is "real"?
Bottom line, I think we agree that all photography is "art", but I think people may mean different things when they say "art". Art doesn't have to mean artificial or interpreted. (After all in paintings there is "realism" as opposed to "impressionist", for example.)
I think we all have lines that we draw as to where things become "Photoshopped" to excess (in our minds). If a photog want to produce an in-camera JPEG and do no post-processing, that is fine with me. But I'm not under any illusion that it is more of a "real" photo than one where the white balance was corrected, or the dynamic range was adjusted to fit the output device (for just 2 examples).