There are two dangerous, interconnected ideas. The first is simple enough: the idea that history is a constant march towards social progress, where any backslides are temporary hiccups.
The second, more complicated one is an overly materialist view of history – that is to say, judging the quality of life in an empire simply by the variety of goods available, rather than how those goods were obtained. A view of history that leaves out some of the most important aspects of daily life: autonomy, freedom from fear, and the ability to have control over one’s life and surroundings.
A friend once asked me what it might’ve been like to watch the shift from Roman occupation to “the Dark Ages,” implying it must’ve felt like a great loss to witness it. I pointed out (with what I hope was tact and factual accuracy, both of which I often lacked in younger years) that the same ‘collapse’ that took the imported wine and silk and olive oil out of the market places also took most of the slaves out of the silver mines and the bloodthirsty tax collectors away from the fields. A provincial governor might be able to build aqueducts and hot baths, but a local chieftain or warlord would speak the same language as you, and if you got together with a few dozen or hundred fellow peasants, you could represent a threat big enough to force the chieftain to listen to you, while to a provincial governor, a few hundred angry peasants would be met with a sneer and suppression by the provincial Roman governor.
It is, in fact, from many of the “touchstones of Western history” that we find the answers to where life began to get so miserable, and realize that issues of social justice once thought to be forever and universal are actually much more recent:
It was the Renaissance that brought misogyny to new heights. It was the printing press and the Luther Bible that brought biblically “justified” misogyny into the homes of shopkeepers and cobblers. It was the Enlightenment that brought “proof” of the “scientifically justified” inferiority of Africans and planted the seeds of modern racism. It was the Industrial Revolution that brought notions of work to their crushingly orderly modern form and made the former agrarian lifestyle of communal, flexible, self-directed work an impossibility.
Every proper noun of Western history that has propelled society forward has done so by dragging the marginalized and the lower classes with them, tying them up and letting their bodies scrape along the road.
I don’t think I’d go as far as this, because if you want to suggest in the primitivist style that all the whiggy stuff actually made life worse then that still implies a linear progression of history except in a bad way, which I’m not sure is any more accurate. Ironic inversion of triumpahlist narratives has a way of supporting those narratives, in the same sense as (for instance) the “white people ruined everything” narrative indirectly entrenches the white nationalist mythos it positions itself against by using its framing as a reference point. History is a murky stew and it would be pretty hard to attribute a narrative structure to if if everyone from the periods described had to sign off on it.
That said, I think there are some useful takeaways from this sort of approach. One, as you say, is that you can’t judge quality of life by diversity of material goods or public works; more generally, that the “greatness” or “importance” of a period from a historical perspective doesn’t say much about how nice it was for common people to live in that period, and a lot of energy is spent obscuring that fact.
The other takeaway is that small local rule tends has a lot of advantages – it takes fewer people to overturn and the ruler is more responsive to your needs. Like, I remember memecucker was complaining about Hawaiian nationalist monarchism recently and my feeling is that while functional monarchism is a lot worse than democracy, the Hawaiians probably still got better representation from a local monarch than they do from a legislature in DC. The reason I don’t go from there to the radical localist/nationalist stance that this is a strict improvement is that lots of little sovereign polities tend to brutally fight all the time, and the only reliable way to prevent constantwar between neighbours is to have them under the umbrella of some sort of larger power. But I do think this makes a case for a significant degree of regional autonomy and representation within larger bodies. The modern US in particular seems inadequately federated for a country of its size and diversity.
The other takeaway is that small local rule tends has a lot of advantages – it takes fewer people to overturn and the ruler is more responsive to your needs.
That is not a good thing.
Or, to put it in different words: “more responsive to whose needs?”
Rulers answer to the stakeholder power-brokers who can push them off their perch. The more rulers you have, the more catering to power-brokers you have. And the further you go down the social ladder, in terms of where the power is centered, the more the local power-brokers are actually going to be interested in messing with with the people around them.
The king wants basically the same thing as most of the peasants, most of the time. The barons really don’t.
This is to say nothing of conflict between sovereign polities, which is also a major concern, as you say.