I asked this a while back. Answer was roughly that job ads aren't substantive and offer little in terms of actual conversation, and repetitive threads that lack

I asked this a while back. Answer was roughly that job ads aren't substantive and offer little in terms of actual conversation, and repetitive threads that lack substance primarily attract people with previous grievances. This would lead to the same thread happening every time the company posted an ad. It makes sense that you wouldn't want to encourage ads becoming actual threads.