Namely, she saw the world in cold, mechanistic, zero-sum terms.

Bingo! One can share Rand’s theology but nevertheless see the world as a plus-sum place. Cooperation, including forced cooperation, can be a winning strategy. Morality merely reifies and internalizes that vision.

Religion provides a bottom-most “turtle” for those who need a “source” of morality. Atheists get their morals from game theory. But either way, Rand’s seminal mistake is zero-sum thinking. All the rest, as the sage said, is commentary.