it's a throwaway. it's 70 day old because two or three controversial comments in a row get accounts without 100000000 karma ratelimited to one comment per infinity. when it happens I make another. my squeaky clean main account is older than yours.
It's a throwaway troll account. I know of three other accounts of the same user. The issue is not a couple of slightly downvoted comments, it's persistent trolling.
The ability to create new accounts so easily and be a nuisance is my least favourite "feature" of HN.