The majority of the ~5 million that covid killed would have been dead of old age, heart disease, etc. in 5-10 years anyway. Covid just shaved off a few years of life expectancy; the same people would have shown up in CDC death counts as heart disease or natural causes statistics a few years later. With the 28k killed by terrorism, not so much. You have a lot more young and healthy dying with decades of life expectancy remaining.

Same with comparing covid deaths to WWI deaths. On the one hand you have thousands of healthy 18-year-olds dying, and on the other you have thousands of elderly, obese, and sickly people dying. Not quite a fair comparison.

We'll see, it's a falsifiable prediction, which is good, but we won't really know until we get the excess death numbers for the next 5-10 years.

Even in the 25-44yr age range, we see a pretty significant increase in deaths: https://www.cdc.gov/mmwr/volumes/69/wr/mm6942e2.htm#F2_down