That does not make much difference to CIA or NSA to my knowledge. There are many ways to correlate pseudonymous with your real identity: IP address, usage pattern, speech pattern, or even patterns in the photos that you posted.
That's way I never used pseudonyms, they are practically useless in hiding your real identity. Additionally they give you a false sense of anonymity.
I'm not worried about state-level attacks (unless I become famous). My opinions are not that scandalous (maybe 0.1% are; but that isn't on HN ;). Many (a small percentage, but a large number) people have similar ideas. If my real identity were released, people may disapprove of some ideas; but I'll be fine.
It's kind of like pictures of naked me. I don't want it to be public but it's not that severe either.
I think it is a social norm in the English speaking countries to not use real name on Internet forums. So I wouldn't call the use of nicknames or Internet handles examples of pseudonyms.
Also, I have no intention of using this nickname to hide my identity. You can Google it to find everything you need to know about me.
That's way I never used pseudonyms, they are practically useless in hiding your real identity. Additionally they give you a false sense of anonymity.