I see no reason at all. Can anyone explain it?
I didn't delete it, but I agree with the mod who did 100%. That was noise. It was a joke, frankly not a very funny one, which was posted as an answer. The entire content of your post was this:
I think it would be a good idea to suspend all too high-rated people like Oli, Rinzwind, etc. for a year or two to let other people do something useful ;-)
That is clearly not answering the question, and not providing anything useful to the discussion. What's worse, it was posted on a pretty serious subject where the suspension of a high rep user was being discussed. That isn't something we (mods or users) take lightly so that makes your post even more delete-worthy.
But the main reason it was deleted was for the same reason anything on the site is deleted: it wasn't answering the question. If you felt it was so important, you should have left a comment.
Firstly there is not really something universally dubbed a "post" here in AU. There are comments and answers.
Comments can be deleted or moved to discussion when the thread becomes too long, too much like an extended Q&A or too jovial.
Answers can be converted to a comment when a user doesn't have necessary rep to post a comment. Answers can be deleted when they are too personal or off-topic. I think your answer is rather a bit of both. This is how I would judged your case.
As far as assertion of being the answer being funny goes, I put you right up there with Muru as not being funny. Which is not a bad thing. I think yours and his answers are usually intelligent, succint and highly educational.
On this so-called answer of yours, whether it be construed a comment or not, I think suggesting banning Oli and/or Windy is over the top.
If you like a good joke though, I suggest trying our watered down Alberta Beer instead of Russian Vodka :)