Maintaining identity on networked, multi-user resources involves giving every user account a unique name.
However, somewhere along the way, the Internet has turned this little bit of administrivia into a culture where that little name is somehow supposed to be your name, your special unique alias that says something about you and identifies you to everybody else. Of course, simple names often aren't unique across the entire web (it's not like accounts are somehow magically synced wherever you go), so people end up having to make up weird names, annoyingly overlong names, or names composed of unpronounceable garbage. And then a decade or two roll by and here we are talking to people with names like BobnarWillowleaf, xxxAwesomeDemonManxxx, and MeTaLLiCa92.
I'd prefer to just be addressed by my real-person name, thank you very much. Which is why I discretely tell you what it is.
-- Alex