In it, he observes
Superbeings would of necessity in any system of government evolve into a sort of aristocracy.
Well, in one sense, yes, but in another, it would turn on: are these abilities of theirs hereditary?
If they are, of course, you have prime aristocracy territory, particularly if acquiring your own from mundane origins is rare and difficult. If they are a random grab bag that, say, normally hit about puberty, things are different. If they are a random grab bag that could hit at any stage in life, things are different again -- you could always, in theory, join their ranks, and you know that their children are no more likely than yours to do so. I would expect parents (in the first scenario) and random individuals (in the second) to seek out any way to trigger it, even if that means haring after improbable or even impossible causes.
I note that having the children of the supers be unpowered will not be all to the good. Elective monarchs are more likely to loot the country for the benefit of their own family, because it's hereditary monarchs who can expect any good they do their country to profit their children.
Most super-worlds seem to go both routes: random individuals get it, but usually their children do afterwards. This would, at the very least, lead to a very permeable aristocracy. Anyone could dream of it. In most, in fact, anyone could aspire to it. To be sure, money and brilliance are both needed to trump dumb luck, but there are "super heroes" who got that way by the dint of working real hard in most super-worlds. Like, say, Batman.
This is one thing that I often see overlooked in world-building: how your societies reproduces itself. For instance, in a world where child-bearing is completely voluntary, wanting to have children selected for, hard. Wanting to have lots and lots of children is selected for even harder. When the ability is new, there can be those who do not want children, but that trait is being selected against -- and it's just a change within a species, not a new species. Evolution will occur. Because this will increase the percentage of those who want children, it will also produce a society in which wanting children is the normal thing -- which, ironically, by social pressure may keep the "do not want children" genes going on, by pressing those who do not want to be parents into the task.
Raising the children also matters. A cyberpunk society can indeed maintain itself by letting children run feral in the streets; indeed, too much TLC for too many children would do much to undermine a cyberpunk society. But if a society needs well-disciplined, well-educated children, it can't let parents raise their children on whims, and freely sacrifice the children's education and upbringings to the adults' desire. At least, it can't allow it long. The majesty of the law, or the disapprobation of society has to discourage it, strongly. (Enclaves can have it, but they are going to be problems.)