Several posts for which the Great Answer badge was awarded were erased (for lack of a better term).
(post deleted or otherwise unavailable)
I didn't think it was possible to completely remove posts from the site. In fact, most other posts in that list are deleted and still visible to 10k+ users.
This questionThis question is about revision deletion, but doesn't mention whether whole posts can be erased.
This topicThis topic is the only mention of that message on MSO, and it was just a bug there.
What's going on here? Is it a bug? Were those posts deleted deliberately? Is it possible (e.g. for the developers) to completely erase posts, and when is this done?