My comment was written with the summary of that article in mind (I didn't make this clear):

> Climate change is going to significantly and negatively impact the world. Its impacts on the poorest people in our society and our planet’s biodiversity are cause for particular concern. Looking at the worst possible scenarios, it could be an important factor that increases existential threats from other sources, like great power conflicts, nuclear war, or pandemics. But because the worst potential consequences seem to run through those other sources, and these other risks seem larger and more neglected, we think most readers can have a greater impact in expectation working directly on one of these other risks.

There is an excellent chapter on the existential risks associated with climate change in Toby Ord's book The Precipice, which you can get a free copy of at https://80000hours.org/the-precipice/