The SM57 is a great mic in some situations. A lot of situations even. But saying that an artist can use an SM57 or an iPhone mic on a hit record and is sufficient is missing the point.
Steven Soderbergh has shot several feature films on an iPhone and the movies were still great, but they're nowhere close to unlocking the full potential of visual expression that you'd get with more refined tools.
Artists who are serious about their craft will keep an SM57 and an iPhone mic in their color palette (Frank Ocean comes to mind), but that's all they are for serious practitioners: a creative choice.
