Agreed. Vulcanized rubber tires appear to be the major missing component. Vulcanization wasn't discovered until 1839 [1] and the need to further improve ride co

Agreed. Vulcanized rubber tires appear to be the major missing component. Vulcanization wasn't discovered until 1839 [1] and the need to further improve ride comfort (from solid rubber tires) helped spur the creation of the pneumatic tire in 1888 [2]. [1] https://www.britannica.com/technology/vulcanization https://www.britannica.com/technology/vulcanization [2] https://www.britannica.com/technology/tire#ref117797 https://www.britannica.com/technology/tire#ref117797