> But unless we have some reason to think that such changing moral feels are tracking some key features of our changing environment,
There is one key feature that explains and in fact requires rapid cultural change: increase in technology (and the increase in wealth that results from it). Medieval agrarian cultures cannot exist in our modern technological world. Those cultures were a result of people being poor, uneducated, and isolated. The memes from those times do not survive - have not survived, and cannot survive - in an interconnected world. There's a marketplace of competing ideas now, not just what the parish priest told you, and a lot more options for what you may do with your life than just "farm the land as a serf." And medieval serf memes are simply maladaptive now; there was a lot of widely accepted violence that would get you tossed in prison now, and the devaluing of education, even literacy, would make you unemployable.
You can't go back without destroying the technology, e.g. a nuclear war. If you're a conservative regressive, you can try to revive authoritarian, tribalist memes, but there's a lot more to being a medieval peasant than that. You get a Frankenstein's monster of a culture rather than anything truly faithful to tradition.
And use your power of reason; look around the world and see where authoritarian, tribalist memes thrive. Authoritarian states; Russia, China, Venezuela. Where these traditional memes thrive, GDP is low and people's lives suck. It's not really surprising, because freedom lets people choose to live the way they like, so if you impose authoritarian dictates then people have to live in ways they don't like. See https://en.wikipedia.org/wiki/The_Economist_Democracy_Index
The tribalist ethos, on a national scale, tends to result in wars of aggression and genocides.
If what you're really concerned about is the birth rate, decline in birth rate closely tracks wealth. Wealthy people, especially women, have more attractive options for what to do with their lives than popping out babies; it's that simple. It takes poverty and oppression to reverse that. (Or DNA evolution, to make reproduction more attractive than alternatives again; or tech solutions, like vat babies).
My point is that its not enough to notice that an environment has changed to justify particular goal changes. You need enough data in that new situation to suggest which changes would work better.
You can use your reason and judgment in the specific values in question rather than speaking in vague generalities. The specific medieval values that regressive conservatives seem upset about losing are authoritarianism, tribalism, and oppression of women. There is plenty of data on what societies look like when there are high levels of those: they're poor, stupid, and unhappy. And the tribalist value leads many of those societies to commit genocides and wars of aggression.
Take a look at https://en.wikipedia.org/wiki/List_of_genocides and you will find virtually all of them were committed by an authoritarian tribalist state. Holodomor? Check. Holocaust? Check. Uyghurs? Check. Darfur? Check. etc.
There is some controversy among historians over whether the Holodomor was an intentional genocide. https://en.wikipedia.org/wiki/Holodomor But if you are accepting that it was the result of the USSR being hostile to the nationalism of Ukraine, then that's clearly tribalist. They can be hostile to Russian nationalism too; the tribe committing genocide in this case would be the Communist party, not necessarily the Russians as an ethnic tribe (although, honestly, that probably played a role). A tribe can be any group of people bound together by shared culture, and does not necessarily have to split along ethnic lines.
The Amish are modernity-resistant agrarian subculture, and they are capable of not only surviving in the modern world but growing faster than the non-Amish society around them. If they kept growing I expect they would hit limits, and their pacifism in particular is not an ESS, but they serve as a counterexample to your claim.
The Amish don't live like medieval peasants. They take advantage of a great deal of modern technology and participate in the broader economy, and only 10% of them are farmers now. They have above 90% literacy. They aren't Catholic; they have religious beliefs and cultural norms of self-effacement that would be unusual in any time. They don't serve feudal lords. They don't do public hangings or publicly torture cats for entertainment. They're pacifists. In short, they have a strange new culture of their own.
Well, they aren't like early modern agrarians either, for all the reasons I just mentioned. And note that the early modern period was the result of the rapid cultural change of the Renaissance.
If you accept impact on population growth rate as a proxy for whether something is adaptive, then - on average - DNA evolution has been adaptive overall recently (world population is still growing) and cultural evolution has been super-adaptive recently - cultural variants are growing explosively - with constant creation for new forms and little communal forgetting.
> But unless we have some reason to think that such changing moral feels are tracking some key features of our changing environment,
There is one key feature that explains and in fact requires rapid cultural change: increase in technology (and the increase in wealth that results from it). Medieval agrarian cultures cannot exist in our modern technological world. Those cultures were a result of people being poor, uneducated, and isolated. The memes from those times do not survive - have not survived, and cannot survive - in an interconnected world. There's a marketplace of competing ideas now, not just what the parish priest told you, and a lot more options for what you may do with your life than just "farm the land as a serf." And medieval serf memes are simply maladaptive now; there was a lot of widely accepted violence that would get you tossed in prison now, and the devaluing of education, even literacy, would make you unemployable.
You can't go back without destroying the technology, e.g. a nuclear war. If you're a conservative regressive, you can try to revive authoritarian, tribalist memes, but there's a lot more to being a medieval peasant than that. You get a Frankenstein's monster of a culture rather than anything truly faithful to tradition.
And use your power of reason; look around the world and see where authoritarian, tribalist memes thrive. Authoritarian states; Russia, China, Venezuela. Where these traditional memes thrive, GDP is low and people's lives suck. It's not really surprising, because freedom lets people choose to live the way they like, so if you impose authoritarian dictates then people have to live in ways they don't like. See https://en.wikipedia.org/wiki/The_Economist_Democracy_Index
The tribalist ethos, on a national scale, tends to result in wars of aggression and genocides.
If what you're really concerned about is the birth rate, decline in birth rate closely tracks wealth. Wealthy people, especially women, have more attractive options for what to do with their lives than popping out babies; it's that simple. It takes poverty and oppression to reverse that. (Or DNA evolution, to make reproduction more attractive than alternatives again; or tech solutions, like vat babies).
My point is that its not enough to notice that an environment has changed to justify particular goal changes. You need enough data in that new situation to suggest which changes would work better.
You can use your reason and judgment in the specific values in question rather than speaking in vague generalities. The specific medieval values that regressive conservatives seem upset about losing are authoritarianism, tribalism, and oppression of women. There is plenty of data on what societies look like when there are high levels of those: they're poor, stupid, and unhappy. And the tribalist value leads many of those societies to commit genocides and wars of aggression.
I think you are projecting your wishes onto less obvious data.
Take a look at https://en.wikipedia.org/wiki/List_of_genocides and you will find virtually all of them were committed by an authoritarian tribalist state. Holodomor? Check. Holocaust? Check. Uyghurs? Check. Darfur? Check. etc.
Or look at the map at the top right of https://en.wikipedia.org/wiki/The_Economist_Democracy_Index . Do you want to live in any of the red (authoritarian) countries?
The data is clear. It's been clear since Orwell. Where's the ambiguity?
I don't think the USSR was tribalist. They were hostile to the nationalism of even the Russian ethnic majority.
There is some controversy among historians over whether the Holodomor was an intentional genocide. https://en.wikipedia.org/wiki/Holodomor But if you are accepting that it was the result of the USSR being hostile to the nationalism of Ukraine, then that's clearly tribalist. They can be hostile to Russian nationalism too; the tribe committing genocide in this case would be the Communist party, not necessarily the Russians as an ethnic tribe (although, honestly, that probably played a role). A tribe can be any group of people bound together by shared culture, and does not necessarily have to split along ethnic lines.
The Amish are modernity-resistant agrarian subculture, and they are capable of not only surviving in the modern world but growing faster than the non-Amish society around them. If they kept growing I expect they would hit limits, and their pacifism in particular is not an ESS, but they serve as a counterexample to your claim.
The Amish don't live like medieval peasants. They take advantage of a great deal of modern technology and participate in the broader economy, and only 10% of them are farmers now. They have above 90% literacy. They aren't Catholic; they have religious beliefs and cultural norms of self-effacement that would be unusual in any time. They don't serve feudal lords. They don't do public hangings or publicly torture cats for entertainment. They're pacifists. In short, they have a strange new culture of their own.
Okay, then, early modern agrarians.
Well, they aren't like early modern agrarians either, for all the reasons I just mentioned. And note that the early modern period was the result of the rapid cultural change of the Renaissance.
If you accept impact on population growth rate as a proxy for whether something is adaptive, then - on average - DNA evolution has been adaptive overall recently (world population is still growing) and cultural evolution has been super-adaptive recently - cultural variants are growing explosively - with constant creation for new forms and little communal forgetting.
Moral intuitions are de facto shaped by salience and salience is getting good harted pretty hard currently.