There's Art out there. Some of it is photographs.
There's decor out there, too. Some of it is photographs.
Decor is generally attractive, or at the very least suitable to the environment it's hung in. It might be soothing, warm, in a home. It might be high energy, dynamic, in a business environment. It might be situationally appropriate, pictures of products or clients or equipment or staff. Decor fits in with where it is hung, and enhances that environment in some way.
Then there's a Fake Art. This stuff isn't decor, or at least if it is it's pretty tough to imagine what kind of anti-living environment it would be hung in to enhance. This stuff is often black and white, usually ugly. It might be high contrast urban shadow play. It might be pictures of homeless people, or starving native peoples from far away. It has many of the trappings of Art: the subjects are very much in your face, the ugliness is often studied, clearly intended to separate the piece from "mere decor".
It's Fake Art because there's no idea there. There's nothing there except a sweaty, desperate, desire to be Art. Is the artist being true to himself? Who can really be sure? Still, usually one gets the sense that the artist is not. The artist is instead aping the forms of Art, and wants to be taken seriously. The piece feels outwardly focused, it feels as if it was made not to express the inexpressible, but instead to be Taken Seriously By People.
There's probably a wide grey area. After all, aping the forms of Art is how Art is made as well. Aping them with, I dunno, integrity.
Regardless, I think there's a well-defined thing here, and if you cast your mind about you can probably call some pieces to mind. Earnest, Serious, Photographs that can't get any farther than being Earnest.