That's fair, actually. This is an argument in the article. I would summarize it as "focusing on long-term risks necessarily means un-focusing on short-term ones

That's fair, actually. This is an argument in the article. I would summarize it as "focusing on long-term risks necessarily means un-focusing on short-term ones, and that's bad". Would you agree? The latter part however ("and that's bad") is not well supported at all. That's what the article argues by emotional appeals. For a counterexample, most of the harms of climate change are still in the future, so addressing it is focusing on longer-term risks. And wouldn't it have been easier if we had started addressing it 20 years ago? To use the same example, extreme harm from climate change (e.g. thousands dead from heatwaves) is very likely, but ultimately still hypothetical -- it has not happened yet. The only difference with existential risks is the degree of hypotheticalness. And when the harm is high enough, why not take the somewhat supported hypotheticals seriously?