This is categorically not true. If it were true professional photographers wouldn't waste six figures on high-end equipment. Not only there are visible differe

This is categorically not true. If it were true professional photographers wouldn't waste six figures on high-end equipment. Not only there are visible differences - smoothness, sharpness, colour balance, the overall look - but some effects and looks are impossible without expensive tools. Especially in difficult light, or challenging shooting situations. And then there's the workflow. The difference is more that amateurs and prosumers never reach the point where the equipment limits their talent. Top professionals reach that point fairly quickly because they just can't do some of the things they want to do. The iPhone is no different. It's a decent video camera and may be starting to edge against some of the mirrorless/SLR prosumer cams. But it doesn't have features that are standard on ARRI and RED. You can make some videos with it, and if you have talent they'll be good. But you can't make all currently possible videos with it. No-compromise professionals are going to understand the difference.