We’ve never called them ‘epileptics’ – we call them ‘people with epilepsy’ because they are people who happen to have that disease. “Whereas now the trend is to say ‘I am autistic’, rather than ‘I’m a person with autism’.
I honestly see no point in this particular language game.
I'm not going to stop saying "I'm allergic" or similar, and it in no way implies I'm incorporating allergy into my personality.
If people are going to incorporate a given condition into their personality, they are going to do it however you spin the words around.
Also, it seems to me that identifying with a disease or a condition to the point that it becomes a key piece of one's mental identity is a new thing, while saying "epileptic" or "autistic" is not. So I don't think that supports the writer's argument either.