Most people think that photography is photography. That, if you own a camera, you are a photographer. With the advent of mobile phones, everybody is a potential photographer. Mobile phones take some of the best pictures I have ever seen. But that's just it, isn't it? It's the phone that is taking the picture. The mobile device decides what ISO, film speed, aperture, etc to use.
I ask you to think about what goes into making a "good" picture. Composition is important, but technical knowledge such as "what ISO, film speed, aperture is called for is just as important. Real estate photography is quite unique as it relates to the other types of photography. When shooting a home or business, I don't necessarily have to worry about assembling or posing live people for a portrait. My subject is still. My goal is to capture the property in a series of pictures to help the viewer better understand the space. It is a relatively standardized form of art, but each property has an undeniable personality that often-times eludes the best photographer.
So, real estate photography IS art! Yes, it requires a technical knowledge that can be learned but it also demands an almost intuitive understanding of perception and experience.