People aren't going to start walking & cycling instead of driving, especially if the cost of a short drive is peanuts compared to today's cost of buying a car or hiring a taxi with a human driver driving you. The world(especially Western world) is filled with fat, unfit, elderly or infirm people. These people are not suddenly walking a mile to their work or to a dentist appointment.
However, you do make one good point. Tesla do forsee car purchases for individual owners own use dwindling at some point in the future. It's then robotaxi's all the way down, either through Tesla directly and maybe to privately owned robotaxi fleets.
Plenty of experts have concerns & fears with the future of AI. These experts know the field far, far better than you or I. It doesn't mean these fearful experts are correct, just that the AI field is filled with people of competing fears and hopes. What I do know is that your settled opinion on such a high tech matter is utterly irrelevant and utterly ignorant.