Right, so for the purposes of predicting what will happen on our actual planet, on which our continued existence is dependent, this is a very loose upper bound

Right, so for the purposes of predicting what will happen on our actual planet, on which our continued existence is dependent, this is a very loose upper bound right? I'm not claiming that knowledge of where the boundary values lie is somehow epistemically unavailable. But there's some important, lower, unknown value, beyond which a bunch of very bad stuff will already happen, and learning the exact values through experience is extremely costly. In the context of responding to this report which is saying "we have already crossed the boundaries! (and we should immediately try to course correct)" rather than squabbling about "well, do you really know the boundary on each of these factors", I think the more honest and pragmatic reframing is to say "we don't know where the boundaries are, but we're headed rapidly away from the known safe region, and we should turn back immediately."