statistics around covid-19 are still tentative, but estimates in published papers (ie not numbers from news reports) have fallen from 0.6 to below 0.3 over the course of the pandemic. i've generally plugged in .1 for lowballs and .5 for highballs, and .3 has tended to give more accurate results, as it plays out.
so, the difference is really not great in terms of total loss of life - it's a factor of 2-3. it's more that the flu kills far more young, healthy people and covid is more fatal in older people.
i would call on twitter to correct it's mistake and republish the president's post.