Most of Argentina is mountainous (The Western side), which has extreme cold temperatures which makes it a popular skiing destination for tourists, it also happens to be not as populated. However, what makes Buenos Aires so different is that it's along the ocean, which makes it a much more livable and sustainable climate, it also gets a large economic boost because it has a large docking and trade system located there.
Examples of this would be other lightly populated rough climate countries such as Mongolia, which has only a population of 3 million despite it's large land borders.