When I started posting I was in a career where keeping moderate anonymity seemed sensible. Now it makes more sense to use something closer to my real name (though conceivably I'll want to change back in future).
As far as I can see in user settings, there's no name change option?
(This is something we haven't edited from LessWrong, so this is me speaking for why I agree with their call, not why I made it myself.) I'd say it's a little of both. I'd like to allow users to change it if it's important, but heavily discourage changes that lose continuity of user identification without much gain. If you have to talk to a human to do it, you're only going to do that if you think it's important. Maybe in the ideal case we'd do something like facebook, where they let you do it, but discourage you through multiple levels of "are you sure?" and "you won't be able to change your name again for x days". And/or we could implement moderator review. But we probably won't prioritize building these, as it seems like a lot of UI functionality that will be very rarely exercised, which is a recipe for bugs.