And the sad thing is, in this respect Chicago is less bad than a lot of other towns and cities in the US and way less bad than many (most?) cities in other countries, including many that are much more progressive than the US. Chicago has been working on curb cuts for years and is in the midst of a years-long quest to upgrade all El (metro/subway) platforms for accessibility, and the ADA---33 years old---has much stronger requirements than, as far as I can tell, even current legislation elsewhere. In Canada, France, Spain, Germany I've seen whole rows of storefronts that are a half-storey up or down from street level, curb cuts are rare, and it's more usual for stores and other business to have steps than not. In other realms of accessibility, I've also noticed a lot more Braille and/or headphone access on ATMs and public kiosks in the US, and fire alarms that are rigged with lights as well as sound.
It's not a perfect mechanism, and the US gets a lot of other things wrong, but the ADA is something we got really, really on the right track (and keep improving).