same here
Old thread I see, but nvm!
If a HoH person can do the job by having a useful level of hearing, then there's no reason why they shouldn't be able to fulfil this role. However, if they're unable to hear at all, it's unlikely that they will be able to do the job safely. Communication is one of the main priorities for this role, so it's imperative that one can communicate both efficiently and effectively.
Many people believe that F/A's are mainly there to provide a waiter service. While this may seem the case, it's far from the truth. Most of their training is safety related, I.e. performing evacuations, educating and accounting for PAX. Someone with severe or profound hearing loss is very likely to struggle, to the extent that it could potentially compromise safety.
It was something I wanted to do myself but after a lot of research, that's pretty much the conclusion I came to. That said, I live in the UK and discrimination on safety grounds is perfectly acceptable here. I believe some countries are anti disability discrimination on all grounds, at least by law.