[1] reality is also somewhat in question in the films universe
At least that's my recollection. I've watched the matrix a few times :)
It's worth remembering that the Matrix is an allegory for systems of labeling and control (notably, gender), which make life (and specifically life with others) easier, though not necessarily better. The Matrix sustains the large human and machine populations amidst Earth's ecological collapse; people who choose Zion choose a harder life where they are free to be themselves. However, when Zion grows large enough to threaten the system, the system comes after its residents and wipes them out.
One person's freedom is tolerable, even necessary for the system to continue; everyone's freedom leads to everyone's doom. The movies have some weird-but-rational implications.
...Sorry, I lost track of my point, which is that we're already in The Matrix. The Matrix is society.
One individual human (Cypher) did choose to be plugged back in, though it didn't work out for him.