Why do you think the real name is important? I think that there are so many people in academia whose position is precarious and subject to the whims of people in powerful positions - many of whom have ego issues. It would be great to have an anonymous forum that the community used to discuss the current state of their field where people could be more open about their (potentially controversial) opinions. This could work out better for science.
A statement about scientific research should stand on its own merit, regardless of who it came from.
Who it comes from is part of that merit - there's a big difference between some untrained person shouting "correlation isn't causation" when it was never implied in the first place (ie every thread on reddit that references any sort of scientific article) and someone who has a deep background in the specific niche that the paper addresses.
Peer review is to be done by one's peers, not some random anonymous commenter.
I think for an open discussion it is important to know who is part of the discussion. As an author you are putting a paper out there, and you do your best to make sure the paper is original, relevant and correct. As a commenter, you should also try to do your best, and the best way to assure that in my opinion is to attache prestige not only to papers, but also to comments. This includes negative prestige for making bad comments. That's why I would say a real name policy is important.
A statement about scientific research should stand on its own merit, regardless of who it came from.