Well, I joined the forum around three months ago, so I think I qualify By way of background, I'm very much an amateur - I'm studying maths and physics with the Open University in my spare time out of personal interest.
I haven't yet posted on the forum, but I have very much enjoyed reading and feel that I've learned a lot from being here already. What has really struck me in particular is the quality of the moderating, and the fact that the mission of the forum as somewhere to discuss science is so enthusiastically policed. As a science amateur, it's brilliant from my point of view to know that I can trust what I read here, because anything that's not rigorous or properly evidenced is immediately flagged as such. And I love the occasions where I read a post, think "that sounds dodgy to me", and have that backed up by the responses, because it allows me to check and refine my own critical thinking process.
Ultimately, if people don't like the way the site is run, they can go elsewhere. Clearly your current moderation policy is okay with the large number of posters who do stay here. If I think anyone should change how they approach the forum, it's people like The Angry Intellect who take such a hostile approach to people who are volunteers running what is, essentially, a free service. It's that kind of posting which makes the forum less welcoming to newbies, not the moderation.