"counterpoint to the cars - they are much more efficient, they can delivery many orders at once"
I'd like to see the math before I agree cars are more efficient, at all. Little electric robots produce a lot less emissions than a gaming PC. Cars...well, they produce a lot more emissions than a gaming PC. And, gig workers are usually carrying two or three orders, not a big stack. In the old days when the only delivery was pizza and Chinese, they could stack them up and make it efficient. These days, it's three different stops at three different restaurants.
"plus disabled people have already their carers to take care of the food"
You have imagined a specific type of disabled person living in a specific type of world, and it is unlike anything that exists in the real world.
Most disabled people do not have in-home carers, at all, much less 24/7. Many disabled people can meet a delivery at the door or sidewalk, but can't easily travel to pick something up.
Sure, most regular folks should walk more, rather than order a burrito taxi. But, that's not where we are, and I don't know how we get somewhere else. Certainly outlawing little electric robots doesn't stop people from ordering food delivery. Based on what I know (which is not exhaustive, but isn't nothing, I work on delivery robots in a different space), I prefer the robots to the cars. But, the robots should absolutely be held accountable for disrupting pedestrian and wheelchair access to sidewalks.