The thing is that in science it shouldn't matter in the long run whether someone lies or fabricates data. Because the core of science is based around reproducibility and peer review. Over time the truth comes out. If someone is going to be making decisions based upon evidence and peer reviewed studies that have been independently verified multiple times, then it would be silly to think that I'm going to be better at making a decision based on nothing but my own emotions or ignorance.
This is true, which is why by explicitly using what you've outlined here as a definition of science, Comparitive Politics is science. And again, I've talked to several comparativists with PhD's in the field about this system (as well as many other people). The comparativists have ALL (100%) said that pure democracy is the only way to instantiate a world government peacefully because of its passive approach to distributing power. I'd argue that it's exactly the same as what Bitcoin is currently doing- instantiating a world currency passively by simply out-competing all previous forms of currency. An online crypto government will just win-out by simply out-competing all previous forms of government.