Here’s an article talking about it

Quote:

The controversy is sometimes difficult for hearing people to understand. Hearing people often assume that Deaf people would naturally want to take advantage of any method that could lead them to become part of the hearing world — especially cochlear implants, the most advanced hearing technology we have. In reality, that assumption is far from true. To members of Deaf culture, American Sign Language is a cultural cornerstone. Because Deaf children who receive cochlear implants at a young age will likely be educated in the oralist method, they are less likely to learn ASL during their early years, which are the most critical years of language acquisition. For some Deaf parents, that would result in a child who speaks a different language than they do.

The article covers a lot more than that, so I recommend reading it to get the full picture.