They clearly did not have vehicular transport in mind when creating TS4, and newer worlds still follow the same example. Just look at Cavalier Cove in BB; most of the housings there are inaccessible to the main road. I think though SM is the biggest offender of this still; the Spice Market is the only district that's even at street level and connects to roads. The Arts Quarter is more of a heightened plaza connecting to the road, the Fashion District is an elevated plaza that I learned is only connected to the city's supposed subway system, and don't even get me started on Uptown.
