OK, let's hear it.
Well, the article proposes a model based on prior origin-of-life research. Thus the authors assume that certain research questions are already answered. Many of their assumptions are, however, problem areas for RNA-world experiments.
The model on offer is based on chemical kinetics (reaction rates) giving rise to evolutionary dynamics (replication and competition). Essentially, the authors define "prelife" as a system that maintains chemical rules and "life" as a system that maintains biological rules. Prelife systems are subject to chemical equilibrium and reaction rates. Living systems are subject to environmental pressures and replication rates. Therefore, the point at which a chemical system can self-replicate is the point at which the system transitions from prelife to life. Here is how the authors define this distinction:Implicit here is the assumption that biological and chemical systems operate differently. But the authors explicitly compare their model to a bottom-up approach to synthetic life. Usually when people take a "bottom-up" approach, they are assuming that biology is reducible to chemistry. Otherwise it is NOT a "bottom-up" approach, but is based on some other overarching parameter or driving force.
Here is a summary of the proposed model: