I think it's pretty easy to understand. Many in the deaf community adhere to the idea that "we are not broken so we don't need to be fixed." I can certainly see where they are coming from. The idea that they are "less" and hearing people are "more" is for sure nonsense and as I mentioned before, I would never try to convince a deaf person to get a cochlear implant. If they asked me questions, I would be happy to answer. The other thing that I think drives the hostility is that it is a threat to deaf culture. They have a language that is really pretty divergent from English and they have their own institutions. If there were a way to suddenly make all the deaf hear, the tradition and culture would die out and they do not want to see it. The rub is that some deaf people spread disinformation and are very nasty to hearing parents contemplating a CI for a deaf child. I have read it for myself here and there and it's pretty disconcerting. Have not dealt with it personally but I suspect some would have a problem with me and my implant, but for heaven's sake, I did not start losing hearing until I as in my late twenties, and did not get to the point of a CI until I was around forty. For me, it was important for me to be able to function in the hearing world because the hearing world was my world. I had a job a kid, a wife that hated my guts just like everyone else and the choice of declining to get one or just taking the processors off and settling into a quiet existence was not something I could do.