Posts commenting some achievements of math.SE users have been posted quite often on meta. Usually it was about a user reaching some reputation milestone, such as 100k or 200k. (I also remember a post congratulating some users on reaching 10k votes, which also contained a suggestion for a badge - so the purpose of that thread was not solely the celebration. There was another post about a user who offered 10k+ in bounties. I do not recall from top of my head some other kind of celebratory post directed to single user. There were some posts mentioning some milestones of the site.)
Recently another user passed 100k, which prompted other users to congratulate them here (now deleted by the OP, with score -2) and here (at the moment four close votes, score -2).
Moreover, it seems that some user2 voted to close several older posts of this type.1
In the light of these events, it might be good to know what is the community opinion on questions such as:
- Should congratulations like these be posted on meta? Or perhaps such post should only be made for the first user hitting some milestone?
- What to do with the older posts of this type? Should they be closed? Locked? Deleted? Left as they are?
1Judging by the fact that quite a number of them is in the review queue. See the review queue history, here is an example of a post currently under review. The users reviewing them seem to be voting mostly to leave open so far. I have one small comments on this activity: If the old posts of this kind should be closed, perhaps it would be simpler to request moderators to lock them with leaving the note about historical significance.
2I am only saying that this is very probably caused by a single user. (I cannot know that for sure.)