We use the top of the line cameras and lenses from Nikon and Canon. These cameras range from 16 to 36 megapixels, and produce raw files that are around 40-60 megabytes each. We always have lenses that range from 20mm to 200mm.
Having the right equipment is very important. But the real quality of the images depends on the skill of the photographer. It is the brain behind the camera that makes all the difference. If the photographer can get amazing results time after time with an iPhone, then the process getting there doesn't really matter. (FYI, there is no way to get equivalent amazing results with an iPhone.)