There was a lot of nonsense printed in 3rd edition, but I doubt they actually said that their population figures were limited to only those people who lived within the city walls (and on the surface at that), because that is not how you measure the population of a city.
Wow. Now we're "early modern"? Holy time jump batman. We've skipped forward about six or eight centuries while the rest of the Sword Coast is set about 1500 AD technology wise.
There isn’t really anything to support any part of the Sword Coast being stuck in the 16th century.
Huh? Where is the balloon powered flight?
HAT.
The mines have railroads. There are cannon on the island with the werewolves.
Dude, those are mine tracks, not railroads.
We are talking about the overland trade from the Silver Marches and so on to the Northeast of Waterdeep, that goes by land to Waterdeep then further via boat or caravan.
..? Baldur's Gate is like 600 miles to the South, and the only way to get anything from the Savage Frontier to Baldur's Gate is through Watetdeep via land, or through Waterdeep by docking for supplies for the 600 mile trip.
Yes, exactly. Baldur's Gate is the trade hub of the Western Heartlands, just as Waterdeep is the trade hib of the Sablvahe Frontier. Those are different regions, and the two hits feed each other. And in 1E, they were a similar population size, just over 100k.
Not to and from the Savage Frontier...?
OK, to be clear, "Early Modern" means from 1453 onwards.
You need hard steel to manufacture railroad tracks, they are as much of a technological innovation as steam power, the principle of which has been know since ancient times. You also need hard steel to make the sewer valves that appear in both BG1 and 3. It’s implied that the cloakwood mines were drained with steam pumps (could have been magitech, but that makes no difference).
Greenwood was never much into medievalism, that was Gygax’s thing. Notice how few monarchies there are on the Sword Coast? Greenwood put in specific places for medievalism, such as Cormyr.
