Thank you for raising this question! I feel the same way about square curbs. They are a hazard to anyone using a bike or scooter or mobility device, and prevent people from taking refuge off the street. I've heard my city argue that they're safer for pedestrians because they keep cars off the sidewalk, but I routinely see cars parked with two wheels on the sidewalk over a square curb, so clearly they're not a major barrier for an out of control vehicle. I haven't found any research supporting the argument that they're better for people walking. Anyone know of such research?
Just last week we had a lot of snow and ice, and while picking my kid up from school I watched a kid using a wheelchair use the bus lane (which was a sheet of ice), because the crosswalk ramp was iced over. The kid had one chance to access the sidewalk on the whole block because the rest has a square curb. It was awful.
I hope you got out of your car and helped him onto the sidewalk.