You are correct that American wines are much more likely to be labeled with their varietal, and European wines with their place of origin. However, those places of origin are so closely tied to specific wine styles that it’s really one and the same. Red Burgundy is always going to be Pinot Noir- unless it’s labeled Beaujolais, which is always Gamay. Sure, there are some outliers (white Burgundy is almost always Chardonnay, but there are some bottling a of Aligote and Pinot Blanc) but generally you know what grape/blend you’re going to get from each of these places. New Word winemakers aren’t as tied to tradition (and hundreds of years of trial and error) in what they plant, so you’re more likely to see unusual choices.

Not going to get into terroir other than to say that to reduce it solely to the soil type is the wrong way to look at it. It’s more of a holistic view of the entire growing microclimate, including soil, topography, water table, general climate conditions, etc.

I’m a sommelier and own a wine shop, for what it’s worth.