This is true-ish. Building techniques have a lot of regional factors. How much rainfall do you get? Does the ground freeze? Is the ground dry and solid enough f

This is true-ish. Building techniques have a lot of regional factors. How much rainfall do you get? Does the ground freeze? Is the ground dry and solid enough for basements? Do you need to worry about heating, cooling, or both? Humidity? There are a lot of practical reasons for architecture to differ from place to place even today. At the same time, materials are more homogenous because more of them are engineered and shipped across the country, so that contributes to some homogeniety, as does the media environment.