I was with you until your last line: "It's just the way nature's machinery happens to work."

Machines are purpose-built by engineers. I don't bet you want to imply that. So do you mean mechanics (aimless as in quantum mechanics?) Either way your skirt Ralph's very valid question. Some phenomena is functional, other phenomena is not. Function implies an agent, a beneficiary. So if the universe doesn't start with agency or function, how do the emerge? I'd argue that they emerge at the origin of life, an agent's functional struggle for its own existence, which neither Darwin nor Dawkins explain. To say that a gene is selfish doesn't explain it but attempts falsely to explain it away. A molecule or a pattern within a molecule isn't struggling for its own existence and neither is natural selection which is a misnomer anyway; it's actually natural degeneration, the second law as applied to systems that are in fact struggling for their own existence doing work to outpace the second law.