I agree with all you listed points sir. Vehicle are one of the most world's polluters we have today. The ban of these vehicles would rather stop these pollution or create a space for human to suffer and seek a means for transportation. Animals would be seen as the next alternative, but just like you mentioned it means the prices of these animals would skyrocket as many owners would want to sell at higher rate to make profits. These animals are not also free from polluting our environment, they can also cause pollution to our environment. Inventing electric vehicles which sounds like a good isn't bad after all, but will that ever be achieved? I wish you all the best sir!