To be fair, COVID's death rate has such a strong association with (very) old age, that not accounting for it is quite questionable. In the article, Nate mentioned himself that Mormon population is 100x higher in Utah and that's a significant effect. The COVID death rate of over 85 years old is more than 100x higher than the very young.

I'm not questioning the results, just that accounting for age when analyzing COVID is definitely a reasonable question to ask for any conclusion.