That is certainly a valid perspective; however the flip side is that the child may be limited in their ability to choose other (perhaps better?) options once they are of age to consent, because of the potential damage caused when a CI is implanted. It is possible that today's CI technology may be obsolete in 5 or 10 years, potentially "closing the door" for future possibilities.
As a late-deafened adult, I agonize over this decision for myself. I have chosen to accept my "Deafhood" and learn sign language, knowing that some situations would be easier if I could "hear". There's clearly no right or wrong answer, one simply has to decide for oneself or one's children based on best available knowledge and what is in one's heart.