I'm not 100% sure, but as far as I know, Bolivia's winter, which is also called the dry season, doesn't usually get a lot of snowfall. This is why most photos of snowy areas of Bolivia show rock and dirt sticking through the snow. Now granted there are exceptions, like they recently had one of their worst winters in 20 years, with blizzards in La Paz, and 10' or higher snow drifts, but that is not common.
Typically travel sites usually recommend taking a lot of sunscreen for Bolivia's dry season. I get the feeling it's a lot like the high mesa areas of Colorado, where they get X amount of snowfall at certain times, then it's mostly sunny and dry, and the snow turns hard, like Fruita's Grand Mesa for instance. So while Inca Camina in this game may not represent what the snowy areas are always like, I get the feeling it represents well what they're usually like.