I haven’t read Fukuyama or a while and have not read his books. I was influenced a lot by Jared Diamond’s Guns, Germs, and Steel. The structure of modern states has been argued about for the last three or four centuries.
The failing, in my view, is the reliance on a human ruler. That is still not replaceable but will be, I posit, soon and we should be developing the systems that would work with a totally unbiased administrator.
Historically I’m closest to China and it's imperial history combined with the 18th century European Enlightenment. There was an intense but difficult relationship there as China still reigned supreme with the Chinese World Order system but was failing. The fall came at the start of the 19th century and not restored to any real degree until the beginning of the 21st century.
Within the broad discussion, Fukuyama’s and others, of modern state structures I’m suggesting an AI cross between scholar-bureaucrats and Janissaries with direct democracy as the ultimate authority.
My largest concern is the problem of sentient rights and resource management that cannot be subject to human whim. Hence the need to make that technical and logical with creativity and emotion the human realm but limited to avoid the normal human disasters.
I’ve been vaguely suggesting the well-known answer to that as a departure from this planet to allow diversity by colonization. But that is just kicking the can down the astronomical road.