https://www.youtube.com/watch?v=W9qTIdVZO7MSay what you will about the youtube channel, but is it an interesting question with many facets to talk about.
What would the implications for transportation be if cars never existed?
What would it mean for horses, draft carriages, bicycles, railways and planes?
How would the infrastructure look different in your country, state, or city? What would be the consquences for urban planning?
I think it is safe to say that we would rely much more on trains for regional transport, both freight and passengers. Local railways would still be around and connect towns with surrounding villages. Streetcars would be much more common, probably to an extent comparable to the first half of the 20th century. Bikes would be everywhere. As for horses and draft animals, I would imagine them to be banned in cities, but still commonly used in the countryside.
What do you think?