The trick is that doctors need to stop treating schizophrenics like we're sick. They need to start treating us like we're real people that just happen to have a different sense of reality. In a sense, I sort of agree with you, in another, totally not. Depression is also another way of viewing reality. Is someone who's depressed "wrong" about concentrating on the negative aspects of living? No... but I think most people who're depressed would rather NOT be depressed. Obviously telling someone who's depressed to just "cheer up", and "things aren't that bad" isn't going to help much. But like a disease, it's an aspect of yourself you'd rather not have and aren't in total control of, and want to be "cured" of. So the disease model isn't too far from the truth. I don't see how scizophrenia is much different.
You yourself don't really like your symptoms, wouldn't you rather they be gone? So I'm not sure I really understand your point.
I have met (and married) people who "didn't feel normal" when they weren't depressed and would have constant lapses in treatment drugs (even if they worked, which most didn't).
While they didn't enjoy being depressed, they enjoyed "not being themselves" less, or were so screwed up the cause-effect understanding was broken.
Depression while also a complicated and layered description containing many different states, is not similar in that people always want to not be it.