Being deaf is an inherently negative aspect. You either have the ability to hear, or you do not. If you do not, it is a dis-ability. No one wants to lose an ability to do something.

Someone who lives an extensive period of time without an ability may have learned how to live without this ability. They learn to cope and affirm their life with its faults in their current state. Offering the ability they lost and have learned to live without may be declined because of the affirmation of their life as it is. It could be declined because the transition is uncomfortable as well. Either way, being deaf is still negative, they've just psychologically coped well.

If you had the choice, would you choose that your child be deaf or not? That you be deaf or not? If one isn't deaf, would they choose to become deaf or not? This entire argument results from academic nonsense that anyone outside that context can see through.