Should I tell this person to get up from assigned seats which are technically assigned for the disabled
Why do you want to tell them to move?
Because he's being rude and disrespectful
I understand what you mean. People who aren't disabled should not use accommodations that are reserved for the disabled. They should get up to allow disabled people to have the seats.
Yeah, but the person never said they aren't disabled. Would it be rude to ask.
Yeah I think asking them would be rude. They might have a disability that you can't see, and would get offended by the question.