I watched 'Matrix Reloaded' again the other night. (Thanks, sweetie.) I tried watching for what it's worth, without delving deep into the greater meaning of things, like others have done. I noticed one major thing and it's major role in the movie; The antiquated, heavy metal, industrial nature of Zion and the ships.
The first view of Zion is of the monstrous doors opening into the monstrous cave. Oversized gears, weights and cables control the doors, which ache to open and close. Yet, ships float effortless around and land gracelessly within. Then Neo and Counselor Hamann philosophize about the need for the old, creeky machines. All the machines and ships appear old and rusty, like they salavged them from the surface and that's all they've got.
It's the rust that changes the entire plot. If the rusty, delapitated walkway in the third ship hadn't fell when the cripple limped across it, then that operator wouldn't have gotten gorged, and Trinity wouldn't have had to go into the Matrix. Because Trinity went into the Matrix, she dies, but not before Neo makes his choice (because it is all about the choices), and saves her with some cool computer graphics.
But why do they have ships that can hover? Why do they have extreme computers that rain green letters. They have real-time hologram displays of the sentinals. Can't they get some Rust-Oleum and grease?