It just seems obvious to me that "human made thing to transform some set of things into a composite+transformation of those things" is fair use if fair use is to make any sense at all. Since analogously, like you said, in the same way you are taking your experience including experience of copyrighted stuff as a set of things you are drawing upon producing something of your own. All art is derivative.
It makes zero sense to me at all that it's suddenly a problem that art is derived if, instead of artist directly painting something, artist sets up some device that paints something. In both cases "human takes inputs and produces something unique" (not a copy, not a scanner, in case that was not clear from context).
Unless I'm missing something too, but based on what I see so far I just feel like I'm from mars and don't belong here.