I don't doubt your experience at all. The question I have for you is: Can you speak for all deaf people? I'm not saying everyone who is deaf is fine. But I do know that for many (even if a minority), it is fine, and it is different enough that they worry their kid will not have the experience they had, and may have a worse experience (in some ways) with hearing.

It's not a clear cut easy decision. I would say one should understand and respect the parents' decision. They know the factors way better than I do, and likely in many ways better than you do (especially as you don't know ASL).

I work with a deaf person (not born that way, but been that way most of her life). I'm sure she'd pay a hefty sum to get normal hearing - partially because her whole family (kids, etc) are not deaf. Even when she openly talks about the advantages of being deaf. If she did have a deaf child and chose treatment for her kid, I'd totally understand. But if she chose against it, I'd also totally understand.

What I don't get is people insisting they are totally wrong/evil for not pursuing the treatment for their kids. Almost always they don't understand the factors at play.