Better equipment CAN (but not necessarily WILL) help the photographer turn his/her inner vision into a better image. As far as selling an image taken with a phone camera or of that sort to a stock agency I will say that 9.9 out of 10 the image will be turned down due to technical issues, regardless of who the photographer is– unless the photo shows something that nobody else captured and it would make the news worldwide anyway due to the shocking nature of the image.
NACO Photography