I think what it's trying to say is that constructors are resilient (i.e. long lived, through virtue of replication) 'structures' expressed in matter capable of stably holding and repeatably acting on digital information. And once you have a basic constructor, assemblages of these can provide successively higher levels of organizational power. Their digitally error-corrected resilience differentiates them from flash-in-the-pan analog chemistry, and once you have that longevity of structure you can start to have life. I think.

I don't know. I mean, yes, intuitively, life as an emergent property of recursive layers of self-organizing structures makes more sense than life as the continuation of a random walk through chemistry, but whatever constructor theory is, it's not deeply explained here. What are its implications? How does it actually compare to alternative theories?