Unfortunately I'm not even remotely surprised. Deaf and hard of hearing people are often targets of people who can't handle someone not doing what they say. Once those people feel their words aren't being shown proper deference some of them can't/won't stop their emotional response to regain dominance. Inability to comply (especially in someone who appears capable) becomes refusal in their eyes, and they'll just stretch it back to something we should have done to prevent them from feeling insubordinated. Cops are notorious for it.

I'd never even thought that one might need to tell an airline that you're Deaf. It's a difficult experience as someone hard of hearing, but it's difficult in the way dealing with the DMV is. Ideally you have a hearing person with you, and if not you bring a pen and paper to communicate when you need a shoulder tapped, and just run by context cues and writing for the rest.

Also I hope this lady consented to being recorded and posted. I'd be so humiliated seeing discrimination against me go viral