With all materials available, my credence is very likely (above 95%) that something self-replicating that is more impressive than bacteria and viruses is possible, but I have no idea how impressive the limits of possibility are.
Much of the (purported) advantage of diamondoid mechanisms is that they’re (meant to be) stiff enough to operate deterministically with atomic precision. Without that, you’re likely to end up much closer to biological systems—transport is more diffusive, the success of any step is probabilistic, and you need a whole ecosystem of mechanisms for repair and recycling (meaning the design problem isn’t necessarily easier). For anything that doesn’t specifically need self-replication for some reason, it’ll be hard to beat (e.g.) flow reactors.
Much of the (purported) advantage of diamondoid mechanisms is that they’re (meant to be) stiff enough to operate deterministically with atomic precision. Without that, you’re likely to end up much closer to biological systems—transport is more diffusive, the success of any step is probabilistic, and you need a whole ecosystem of mechanisms for repair and recycling (meaning the design problem isn’t necessarily easier). For anything that doesn’t specifically need self-replication for some reason, it’ll be hard to beat (e.g.) flow reactors.