I think that there might be personal or professional incentives towards underestimating or overestimating based on situation, but the moral incentive will always be towards exaggerating your belief.

I feel like there would be a stronger moral incentive for the high doom people to exaggerate, but im having a hard time putting this belief into words.

Oh i probably should have specified that the incentive im referring to is getting people to adjust their own beliefs, not stuff like judgement.

Lemme give an example:

Your friend has p(doom) = 1% you have p(doom) = 10%. You overestimate your belief to 20% to get your friend closer to your truly held estimate. With the hope that the larger the difference, the more your friend will revise up based on your judgement

There's too much incentive to overestimate your own p(doom) when talking to people that have lower p(doom) than yours and no way to check if the probabilities are accurate. (This could also apply to underestimating, although i think incentives are less strong)

This problem seems pretty tough to solve to me, does anyone have an idea on what possible solutions could look like?

It's really bad to leave things out and falsely assume there is shared understanding compared to the alternative.