[Mithaldu]

> if I understand what you're saying, it sounds like our understanding of the probabilities of the two scenarios occurring isn't exactly known

Incorrect.

A complete planet-devastating runaway scenario is much more likely, as it requires merely that humans continue to operate as they are doing right this very moment.

The best case scenario only comes about if we get our shit together.

That's the gap that separates worst and best case: Humans change nothing <---> Humans make a supreme effort. Probabilities follow directly from the probabilities of these two things.

Sorry for not having stated that clearly.