Initially, Zero & One are talking about heuristics for measuring how good something is: maturity, quality of tools, documentation. Then Zero tells an anecdote about someone who agrees with them.
Two rightly points out that this is a terrible decision making process, and then Zero and One start hashing out a way of doing an experiment. They quickly realize that there are way too many variables, and that nailing down a definition of "good" or "better" that can actually be experimentally verified is essentially impossible. All the things they can measure are incredibly specific, and they've got no way of mapping back from there to a general notion of "goodness".
So, what are we to do?
Like Two, we could use the difficulty of making rational, scientific decisions as a reason to stick with the status quo. Or like Manager, we could look to a trusted authority: the crowd; our instincts; a trusted advisor.
Can we do better? Is there a way we can actually use science?