Hockney derived a new theory of art and optics: around 1430, centuries before anyone suspected it, artists began secretly using cameralike devices, including the lens, the concave mirror and the camera obscura, to help them make realistic-looking paintings. ... Hockney suggests, knew the magic of photographic projection.
https://www.nytimes.com/2001/12/04/arts/paintings-too-perfec...
T. S. Eliot’s dictum: “Immature poets imitate; mature poets steal; bad poets deface what they take, and good poets make it into something better, or at least something different. The good poet welds his theft into a whole of feeling which is unique, utterly different than that from which it is torn.”
A trivial example: a nephew of mine proudly showed his drawings. They were really fantastic for his age, and everyone told him so. Turns out, he drew them by putting paper on a computer monitor (this was back when CRTs were still the fashion) and tracing. That did change the perception of merit a bit. The difference in the difficulty underlies the difference in appreciation.
To make my stance entirely clear: this is not meant to condone or condemn either side.