I think that the Matrix was made as a one-off movie, originally. I don’t think they knew how it would be received! Reeves even took just a cut of the action, thinking the film would not really be a big hit. Therefore, the universe is much more underdeveloped than that of Dune. There is one more that people probably do not see: The Animatrix. It is about ten shorts of the Matrix universe that fill in the story line; like how the kid originally shows up, what happened to the sky, and why there was the war between humans and machines.