Complex sentence: Ross had invented the car-oriented urban form, what Reyner Banham called "the linear downtown" later adopted across the US, and contributed to Los Angeles' reputation as a city dominated by the car.
Split into simpler sentences: Ross had invented the car-oriented urban form--what Reyner Banham called "the linear downtown" model later adopted across the United states. The moves also contributed to Los Angeles' reputation as a city dominated by the car.