Eh, the debate is a little more nuanced. Deaf people don't die if they don't get medical intervention, not would most categorize their deafness the same as a person with a missing limb would.

Diabetes also hasn't developed it's own language and culture.

The core of the debate is around children very often. Is it better to have a limited sense of hearing (the implants don't provide perfect hearing. Far from it. ) that can really just make speech intelligible and potentially be shut out from a rich culture that can communicate with you better than you can with the hearing world with the implant, or to be introduced to that culture fully at a young age and make the choice for themselves when they get older, but potentially have the integration be less likely to work or of lower quality?

It's far from the same, but left handed people face difficulties in life. Handwriting is harder, many manual activities in the sports and arts are more challenging to learn, and you're more likely to hurt yourself in any number of ways because the world just doesn't fit with your default.
We long ago decided that we didn't need to correct left handedness in children anymore because it does not impair their quality of life in a way that's worth the cost of correction.
The debate in the deaf community is similar. It's a difference, and it does have difficulties, but many contend that they're not being deprived of anything that's worth the cost of correcting things in a child.