I do not think her expectations were legitimate and do not think her suing the airline because of their refusal to board her is legitimate either.
Now if her lawsuit is that the Airline caused her distress by their rudeness in addressing the problem; that is another issue; although, we do not know what 'she' said. . .before 'they said'.
We could also maybe allow that the 'insensitivity' of this airline rep; may have been the result of her being taken by 'psychological surprise' here. . . .
Paris to New York; while not a 'sky marathon'; could certainly pose some herculean-like challenges, nonetheless. . .and at the psychological expense of the other travelers and/or/if only. . .the 'crew'as well. . .should we get real insensitive, here.
This woman needed an assistant; and still maintain; that her expectations to travel solo, were surely meant to challenge (financially) the airline; for whatever reason. . .
It could be like letting a relative with Alzheimers fly alone and then suing the airline when they got lost. Some people need to be accompanied --- that's sad but that's life.