The primary reason I believe Zion/"The Real World" must be another layer of the Matrix

Simply put, resources.

In a world that's almost entirely nothing more than a massive pile of trash and metallic wreckage, several Zions in a row (with what seems to be a plan for an endless destruction/resurrection of them), there's only so many functional computers, light bulbs, fabrics, whatever they make their protien slop out of, ...whatever the hell hovercrafts are made of, and so on, to be found and put together. Are these freed humans making light bulbs themselves?

In the comics, there are a couple different stories about explorers/hunters/gatherers who go around researching old leftovers of human society, finding seeds to make wheat that one time, finding books etc. If we assume that that impulse is consistent and common to all instances of Zion, each iteration would find less and less artifacts on those expeditions.

How can 20something humans build Zion? Does he explicity choose computer scientists, engineers, carpenters, et cetera? Do the machines just build Zion for them? If so, how does The One explain a pre-existing "last Human city" for them to escape to?

If Zion and the real world are really "real", I don't see how it could possibly keep being made when nothing useful to humans has been in produciton or able to grow for centuries.

Edit: Just going off early replies here, maybe, this being a forum for discussing The Matrix, consider responding to this with your own thoughts about why this is right or wrong based on a reading of the movies and what you think about it rather than just loling and telling me I'm wrong and dumb for thinking stuff that's dumb and wrong.

Jesus christ. You'd think people on a Matrix forum would be more keen to wax philosophical about the Matrix.