Right now it isn't closed. (Incidentally moderators weren't involved either in closing or reopening it; that was just ordinary users like you and me.)
What's been done to it now is a 'lock', which means nobody can edit it or vote on it until it's unlocked. This was done by moderator Keen. Obviously he's the only one who can explain exactly why he did it, but the notice "Content dispute" which he added at the same time suggests that he locked it because there was significant disagreement between yourself and some others about its content. Frequent edits and rollbacks often lead to such a lock being imposed.
You're quite right to take this to meta, as (I believe) this is the appropriate place to hash out disagreements that led to a post being locked. I'm not sure why everyone is downvoting you here.
(FWIW, I have no 'axe to grind' in this issue. I didn't answer the question or vote to close or reopen it, although I may have voted to "Leave Open" when it first appeared in the Close Votes review queue.)