Standard response:
1. No, I wouldn't want a cure.
2. This is not because I think autistic people are superior. It is because I want to be myself, and not someone else. Life with autism is a different kind of life, but it is not inferior, and there are more important things than not being disabled. Being myself is one of them.
3. A cure for autism is impossible, and will likely never happen, because we will find a prenatal test long before we find a cure, and when autistic fetuses can be aborted, research will stop.
4. In order to cure autism in an adult, theoretically, one would have to erase everything you had learned, re-wire your brain, and start from the ground up. It would be like having major brain damage and having to re-learn everything like an infant, and there would be very little of your original personality left. You would most likely not recover fully because the adult brain does not have the plasticity that a very young child's brain does.
I should just put this stuff in a text file and copy-paste it whenever somebody asks this question. It should get used about once a week.