A few thoughts: If things are so dire, it feels insufficient to just "slow down" and just "do a better job".

Why not concurrently publish or commit to publishing an initial audit? How is anyone to judge if this is the right move as opposed to being overly cautious, prudent, or reckless?

Why no concrete proposals about when or how such a pause could end? Obviously incredibly hard if not impossible, but it seems like securing critical infrastructure, web infra, consumer devices, etc would be a prerequisite. Or about how models have to be deployed so as to prevent breaking out of containment?

All in all, for an open letter, without digging into potential motivations or who benefits, it leaves me with a lot of questions.