I think you misunderstand OP. The purpose of citations is to prove facts. The argument made based on those facts does not need a citation.
Much of the time it isn't fair to ask for citations even for specific facts, but that's a separate problem.
Much of the time it isn't fair to ask for citations even for specific facts, but that's a separate problem.
Those cases are covered by b)
But the person you're replying to pointed out other, non-adversarial reasons to ask for citations (which depending on the tone of the question, may be misinterpreted)