Oh, you poor, poor fool.
You have opened the door. It cannot be closed. This is true of all social media, but it is infinitely moreso on Steemit---the social media platform where every post is stored on the immutable blockchain.
Of course, you can edit posts, meaning that you could whittle down your post to nothing. It would no longer appear on the site, but it would remain forever on the Steem Blockchain.
Sorry.
Ok. Thank you for the answer maestro!