If they are delusional, it still doesn’t bring any harm to you OR society, so let them live in their delusions.
I pretend to have delusions in real life, but I know I don’t. I once convinced a friend of mine that I beleived that I was abducted by aliens. He didn’t believe me, but he believed that I believed it.
It was rather funny, actually. I eventually told him I was joking, of course.
You see, having a delusion about reality makes reality much more fun and enjoyable. If Cyborg Dragon IS delusional, then it is a good thing for him, and you shouldn’t try to bring him out of it.
However, there is the SLIM chance that he IS a dragon. And in that case, I think this is interesting.
Please read the post I have in the other thread for more details on that last point.