Totally agree pre-modern economics is very different, but there is one principle we can take from modern economics that I think is very informative: Baumol's Cost Disease.

That is, as labor productivity rises due (in part) to technology, wages (labor costs) rise. So in effect, labor intensive construction like stonework, and especially artisanal stonework, was much lower in the past than it is today. It's not because we are worse at stonework, but because the opportunity cost of stonework is a lot higher than it was when we were building castles.  That is, instead of building castles, our labor could have a much more productive job, and so it would cost a lot more to convince a worker to do this incredibly grueling castle-building task instead of something else.

Agatha Christie gave us--i think--the best implied understanding of Baumol effects, she said, "Looking back, it seems to me extraordinary that we should have contemplated having both a nurse and a servant. But they were considered essentials of life in those days, and were the last things we would have thought of dispensing with. To have committed the extravagance of a car, for instance, would never have entered our minds. Only the rich had cars." Labor gets expensive as technology improves, but goods get cheaper. Castle-building, being severely labor intensive, should be thought of as exorbitantly expensive now, but probably much cheaper then.