They're referring (or at least I think so) to the Dissociative Identity Disorder note. I think they're right, It's a very stigmatized mental illness. In fact, most mental illnesses are stigmatized not only in videogames but in every media. They rarely have anything to do with how they're portrayed. Someone suffering from Dissociative Identity Disorder is as dangerous as any other not mentally ill person. I know it might look like a small thing to you, but many small things like these end up building one huge stereotype. When you or anyone near you is dealing with a mental illness these small things can hurt a lot. My guess is K20fourty was hurt and that's why they jumped instead of giving an explanation (though I understand, when you've given this explanation a hundred times to a hundred different people you get tired of doing so). I hope you understand better now. It's as easy as not addressing mental illnesses unless you do it faithfully Again, it's a small thing but it means a lot.
Ps: English ain't my mother language so sorry If some parts don't read too well.