Why put a number on it? Every number so far has been wrong. Can we agree on the negative impacts of humans on an environment conducive to humanity without putting obviously wrong timings on predictions? I bet your intention is to provoke urgency but to most people it just causes an eye roll because it's not true, whereas the underlying ideas are true.
Weakening predictions until they become unfalsifiable seems like an odd approach to being taken seriously.
cod fishing boats used to have to be wary of the catch being so big that it would tip the boat.
We have no real frame of reference for what we've already lost.
Very much agree. It's a pretty common mistake to bundle real information with obviously wrong details and lose credibility. Especially in the eyes of people looking for a reason to discredit the argument.