Instead of a filmmaker, what if Steven Spielberg deal with oils, watercolors, and acrylics and applied his craft a bare canvas with a brush instead of directing actors behind a camera? Would he have been one of the greats such as Picasso, Van Gogh, or Da Vinci? Or would he have been regarded as some superficial flash in the pan the way some look down on Andy Warhol? It is possible time would have only told and he would most likely had to have been born in a previous era for this debate to hold water, although this not necessarily would have been the case.
There is no denying Spielberg could have easily been born and successful as a painter the post-World War II era (the era he was born in anyway), but indeed the above mentioned artist from previous eras were held to a much higher standard. One reason could be their exhibits were in New York, London, and Paris. As opposed to being available or sold online, much less at your local art gallery or museum.