Disabled people should have to ask for a seat on public transit if one isn’t available; other people shouldn’t immediately get up when a clearly disabled person boards, nor should anyone expect them to without being asked. Similarly, you have no right to criticize someone (who doesn’t appear to be disabled) if they’re sitting in a seat designated for disabled people and they don’t get up when a visibly disabled person gets on.

First of all, the disabled person might not even want the seat. If they do, it’s reasonable to expect them (as an adult) to advocate for their own needs (i.e. ask). It’s actually more offensive to assume that every elderly or otherwise visibly-disabled person is incapable of that.

Second of all, not all disabilities are easily visible. I’m a mid-twenties guy and I was born with an auto-immune disorder that sometimes makes it very difficult or painful to stand/walk. It’s happened multiple times that strangers on the bus have chewed me out for not giving up my seat, even though (statistically) there were probably other people sitting in disability-designated seats that needed that seat less than me and the visibly disable person who just boarded. I can’t fucking believe I have arthritis in my twenties, either. I’m just trying to cope with the shitty circumstances I was given and the last thing I need is to constantly have to justify myself to ignorantly self-righteous strangers.