And we see the same problem again. The number of people who care about the real-name policy is so vanishingly small that it just doesn't matter. It's the 37 Signals cat.jpg[1] issue problem.
Look at Facebook. Everyone[2] uses their real names, and it seems to have done ok.
[1] Apparently some people thought it was outrageous that 37 Signals posted that the 100 billionth (or whatever) file uploaded was called cat.jpg.
[2] I expect some pedantic comments here about how their friend's boyfriend uses a fake name to avoid an ex-gf. If you think that is important then may I suggest you are missing the point.