Oh, I didn't say it had to be mandatory for ME, but I'm saying for those CI professionals and those related to the CI procedure, that is their goal--speech and hearing.
If I ever were to implant one of my future children (I'm honestly wary as to what I would do if I faced the situation), I would choose ASL and speech. But I know some parents think that the CI will just "fix" everything, so they do not need speech therapy, etc. should they want their child to speak. I think that is why they do the psychological evaluation, though it isn't right that the parents MUST go through the speech therapy and whatnot if ASL is going to be their preferred language.
I think it would be better if they established that they will be helping their child adjust to the CI in generally and securing A language, period. Even better if they chose both their spoken and signed languages.
I don't think denying to implant a child is going to solve the parents neglectful ways if they refuse ASL. As long as there is communication, everything should be fine.