A lot of people actually do follow them. If you check https://fns-prod.azureedge.net/sites/default/files/nutrient_... (from https://www.fns.usda.gov/nutrient-content-us-food-supply-190...) you can see saturated fat consumption going down as recommended, chicken consumption going up, even things like sugar has gone down recently. These obviously vary between country, but here in Finland people at large do seem to follow the guidelines especially considering school and work canteens, retirement homes and so on.