Yeah it's been really odd to see the take that self-driving must require strong AI. It needs to be done carefully, but it's clearly a manageable engineering problem if you have good sensors.
Sure it's probably feasible for cars to handle hand signals in the happy path, but anything outside of that will be disastrous. How will the car understand and communicate with a person who doesn't use the standard signals, aside from having some level of intelligence?
Sometimes. Other times they confusingly gesticulate or just shout out things, or even give conflicting signals. Humans can interpret these without much effort but it's a hard AI problem.