Ironically, the question you linked to is exactly the kind that gets closed so often on StackOverflow as being "not a real question" or some such. Thankfully, when they close something it doesn't get deleted.
They do delete worthless questions, spam questions etc.
The example may be a bit off, I didn't put much effort into finding one (I just searched for questions tagged with design-patterns, since this is a relatively "timeless" subject, and I picked one with a highly-rated answer), so I surely could've chosen a better one, my point still stands I believe
