Joseph: “The towns shtetlach’s main road was a dirt road traveled by a few horse and buggy’s each day.”
Sorry these arguments are made by those who don’t know the inyan. Once a road is 16 amos wide you either rely on the criterion of shishim ribo and you can establish an eruv, or you don’t rely on the criterion, and an eruv can’t be made (if there is no other heter).