Remember Cypher, who sold out? We wanted to go back to the Matrix, and one of his demands was what he would be when returning, indicating it's the Matrix what decides, and not the human.

And the Matrix isn't living in symbiosis with the humans, because a symbiosis is benefitial for both sides. Clearly this isn't the case, unless you want to see Neo and his comrades as highly evil people. The Matrix seems like a parasite, draining energy from the humans (they might use cows as well), with nothing real in exchange.

Morpheus compared living in the Matrix with experiencing a dream.

Abigail