I think that analogy works well in his defence though. The "medium" you are expressing would be photography, and I think it would be very likely to be photography of much lower quality than that taken by dedicated still photographers. That's a natural consequence of the fact that each individual frame is not being composed for the purpose of viewing in isolation, but to be viewed for one twenty-fourth of a second as part of a moving, dynamic film production, along with an audio soundtrack of dialogue, music, and foley.