That "as much as" was attempting to account for overloaded medical conditions which will raise the rate, though for 20-44 it'd be unclear by how much. If we go by that table using a 2.3% death rate, that'd already be .3% using a naive literal scaling to the death rate for that age group for the US currently. But yeah, fuzzy numbers and napkin math warning is certainly warranted, I'm nowhere near an expert on this.
As mentioned, the flu death rate of 0.1% is overall as well - for younger people it is also significantly lower, so the increased risk still holds for younger folks. Source [2] shows that well.
I know the numbers are still super fuzzy and it depends on who you ask, but at least according to Wikipedia, the US fatality rate for ages 20-44 is 0.1-0.2%, not near 1% (though certainly at-risk individuals would be higher than the average...)
https://en.wikipedia.org/wiki/Coronavirus_disease_2019#Progn...