Multimodal builds resilience. We should learn from what happened with our car-only America. You are trapped if you don’t have a car (or it isn’t working). Which is why we need sidewalks that are safe, bike lanes, transit lines, and a diversity of “personal mobility devices.” No one mode works for all situations; and only one mode has many failure points.
And that said, of course we need to work hard to make AVs as secure as we can.