The Spanish flu of 1918 killed ~675k people in the US [0] and the US population was 105M [1], so the Spanish flu killed off a bit more than 0.6% of the entire US population, or about 1 in 150 people. Despite massive improvements in sanitation and ability to distance from others, COVID has still killed a bit more than 0.2% of the entire US population in the past 2 years. These pandemics are comparable.