Well, if it goes unchecked, that will be almost everyone. But so far in the US we are a little over 42 million confirmed cases (certainly an undercount, since not every person who got infected got a test, especially early on when tests were harder to get). In 2020, the median age of the US population was 38, so let's use that number for our calculation of risk.
1.4% of 42 million people would be 588,000 deaths (about 100,000 shy of the current confirmed case count). NOT a small number: that's a little more than the entire population of Baltimore, or about 8 Hiroshimas (not to make light of that horror).
And 42 million is not the end of the story: we're still getting almost150,000 new confirmed cases a day, of whom about 2,100 will die if that 1.4% death rate is accurate.
My conclusion: small percentages are deathly serious if the base number is big enough.