Last night we watched "Nell" which is a fictionalized account of a young woman with developmental disability, most of which is environmental. The movie wasn't too popular because it accurately depicted prejudice by normal people against someone with a learning disability. Nell felt life on a more emotional level than our society expects and almost got herself institutionalized.
I saw the movie as a allegory about all people with disabilities, how the differences can result in exploitation (side show), discrimination, abuse etc.
We are a long way from accepting each other as we really are but we should try. The world can be destroyed by people like the Nazi's who carried intellectual argument to the illogical extreme of exterminating those who were not Aryan. Inside of many cultures is a similar desire that is held back by public approbation, but just barely.
The movie will make some people - like the critics - squirm. Nobody said they were not bigots.