There's no scenario where these delivery bots survive US city sidewalks. They will be hijacked, destroyed/attacked, vandalized heavily. The police will not be able to do anything about it. The business model will not survive the US, unless the companies plan to deploy delivery tanks. It'll thrive in safer cities around the world though.
I guess time will tell, but I think most cities in the U.S. have areas that are affluent / on the "right side of the tracks" where robots could traverse unmolested, and then other lawless no-go areas for robots.
True democracy is throwing these damn things in the river.
Or maybe you can ride them like a bronco?
I'm not sure if you'd consider London to be a safe city but these things won't survive in London either.
People are already pissed off about delivery ebike riders, who disobey laws and ride dangerously. But there's very little you can do about humans. A helpless robot that is causing a hazard to pedestrians? A ULEZ-style strike force will be mobilized to drive them out.
And what about blind and partially sighted people? The place for wheeled vehicles in on roads. If you want to exist in pedestrian areas then make a robot that can walk.