In Divinity 2 there was originally going to be an area containing elves and dwarves, but that got cut during development (late enough there wasn't much of an explanation put in the game for their absence, or references to them in other areas, etc).
There was also going to be a swamp (
screenshot 588KB), also cut at some point.
Aleroth was built up during the war with the Black Ring, and during the more than 70 years since Divine Divinity.
In real history, there have been lots of times and places where there was virtually no knowledge of past societies and technology. I'm sure Larian can come up with a reasonable explanation for having steampunk elements in DC.
