Jono's Shortform

P(doom) can be approximately measured. 
If reality fluid describes the territory well, we should be able to see close worlds that already died off.

For nuclear war we have some examples.
We can estimate the odds that the Cuban missile crisis and Petrov's decision went badly. If we accept that luck was a huge factor in us surviving those events (or not encountering events like it), we can see how unlikely our current world is to still live.

A high P(doom) implies that we are about to (or already did) encounter some very unlikely events that worked out suspiciously well for our survival. I don't know how public a registry of events like this should be, but it should exist.

Our self-reporting murderers or murder-witnesses should be extraordinarily well protected from leaks however, which in part seems like a software question.

Yes, this seems unlikely to happen, but again if your P(doom) is high, then we are only to survive in unlikely worlds. Working on this, to me, seems dignified: a way to make those unlikely worlds a bit less unlikely.