Re: Green Antarctica cringe: also the freaky medical stuff and casual mutilation the Tsalal get up to, especially the Cold Islanders, though to be fair with them it's hard to tell how much is in-universe embellishment. There's a reason no real culture views the human body as a trivially deconstructible machine, and it's not just morality and squick. Your malnourished immune-compromised slaves will die of infections if you cut out their eyes because they "work in the dark so they don't need them anymore" Iskr, that seems kind of wasteful and also those germs will spread to your people who are constantly doing questionably sanitary things like mutilating their faces and then wearing human skin face masks.
Really, the Tsalal should have horrible problems with disease given their combination of unsanitary lifestyles and extreme inbreeding (which weakens collective disease resistance). And they have a grimmer version of the "libertarianism is not actually a good social system for a space colony" issue.
I don't think I'd call Green Antarctica the most cringeworthy alternate history I ever read, but it's definitely got a big "these people do not suffer the realistic costs of their way of doing things, at all" problem.
The Draka had the same issue. As I recall, the Spartans (who the Draka are roughly modernized and "amped up" versions of) had to be cautious with foreign adventurism because it was risky to take too much of their manpower away from keeping the Helots down. Going by that once they ran out of easy conquests a culture like the Draka should actually expand fairly conservatively and be almost timid as a geopolitical actor (in ironic contrast with their macho culture and self-image). The Draka just conquer tens of millions of square kilometers of land and huge chunks of the world population in a few years no problem.