I'm disabled and used to use rideshares a lot; I remember one time my ride pulled up, I nodded to the driver, got in the front passenger seat, and started a chat. I didn't notice that he was missing an arm until he physically pointed it out to me, after talking about my visible disability. I laughed and apologized, feeling blind, and he assured me it was fine, apparently lots of people don't notice. I am partially blind though, so at least I have a bit of an excuse :P

Hey, it's me, the person who wouldn't notice for months because that exact thing has happened. In my defense, she did often wear longer sleeves that made it easy to overlook until she handed me a pencil.