@Annette33
I believe that, the Community Managers in some way, does what you have said in item 1. I belive that, when they see some questions or debates that are of great concern to hosts, they may select it to be analysed by the Airbnb staff that works with the help center. If the subjects has to do with ideas to improve the system (even if it is discussed out of the host voice sector), I believe they sent the topic to be read by the right staff.
Honestly speaking, I do not believe that the help system should be better than it is now because many user tends to be lazy. Many of them do not read thouroughly the basic instructions before using the system. Many user want "babysitting". If an internet company puts 1.000 phone number available to help users directly, there will be 100.000 user phoning all the time to ask silly questions!
There will be always a percentage of lazy users that will be always wandering in the forums and communities, and the more a company offer babysitting, I believe this percentage will tend to be bigger.
There are also many user that find difficult to use the system because apps and software are an strange thing to them. It is a kind of "computer challenged user"... and a phone number or direct contact by email will not make them be skilled at once. What they can do is to work hard to get used to apps and computers, and in the meantime they can ask questions in the communities and socialize with other hosts.
If an issue or question is very important or difficult and not a silly question, then there is a phone number ! The more experienced hosts can indicate the phone number to the ones who have a serious question or are having some serious problem.
It is just my opinion and my point of view on ths matter.