Sure, that makes sense, but it ignores the historical reality of the situation. The only reason this city exists in the first place is because there was a huge

Sure, that makes sense, but it ignores the historical reality of the situation. The only reason this city exists in the first place is because there was a huge deposit of silver there that the Incas or the Spaniards stumbled upon. The town grew up around the mines. The easy-to-get-at silver petered out, and they switched to mining copper, then zinc and lead. Eventually, old-style shaft mining was no longer profitable, and open-pit mining replaced it. If you wanted to live a 15th century lifestyle growing potatoes and quinoa and herding llamas and alpacas, you can still do that - people up and down the Andes still are.