This take seems to lack nuance.
If there is a 10% chance of extinction conditional on AGI (many would say way higher), and most outcomes are happy, then it is absolutely worth investing in mitigation.
Obviously they are bullish on AGI in general, that is the founding hypothesis of their company. The entire venture is a bet that AGI is achievable soon.
Also obviously they think the upside is huge too. It’s possible to have a coherent world model in which you choose to do a risky thing that has huge upside. (Though, there are good arguments for slowing down until you are confident you are not going to destroy the world. Altman’s take is that AGI is coming anyway, better to get a slow takeoff started sooner rather than having a fast takeoff later.)