We could consider making a list of similar guidelines that we wouldn't want to enforce generally, but that together could provide a sort of cognitive clean room to discuss super-touchy subjects in.

Great idea. I'd say the biggest useful guideline here is that on mind-killing subjects we should make a norm of only saying the pieces we actually know. That is, we should cite evidence for all conclusions, or, better still, cite the real causes of our beliefs, and we should keep our conclusions really carefully to only what is almost tautologically implied by that evidence. We should be extra-precise. And we should not, really really not, bringing in extraneous issues if there's any way to avoid them.

When people try to talk about AI risks, say, without background, they often come up with plausible this and plausible that, and the topics and misconceptions multiply faster than one can sort them out. Whereas interested interlocutors even without much rationality background who have taken the time to sort through the sub-issues one at a time, slowly, sorting through the causes of each intuition and the sum total of evidence on that point, in my experience generally have managed useful conversations.