> If we weren't conscious we wouldn't know we had slept.

How do you figure? It’s not uncommon to fall asleep, wake up, and be convinced that you never fell asleep even when people next to you tell you that you were unresponsive, snoring, talking in your sleep, etc.

There is a difference between what is experienced in the mind and consciousness. What you're describing are aspects of emptiness (and content or lack of content) as experienced by the mind waking/dreaming/deepsleep. But consciousness / Atman is always aware and awake.