Here's where I think Fauci's number is coming from.
(Before I get into too much detail and as a point of reference, the
CDC reports that 51.8% got the flu vaccine in 2019-2020. The US will soon be above that number for COVID vaccinations. And I hope my numbers below are right!
)
Over the last decade, the U.S. has averaged about 29 million cases and 36 thousand deaths due to influenza each year. Whether you agree with it or not, this is considered "normal". Normal in the sense that we
don't wear masks and we
do run at full capacity. 36 thousand deaths per year means about 100 deaths per day. (Obviously, it's higher during flu season.)
With a population of approximately 330 million, this means that about 9% of the population gets the flu each year, while 0.011% die from the flu each year.
Other data suggests that COVID-19 is 10-20 times more deadly than the flu. Let's go with the larger number of 20 times more deadly.
This means that in order to have what (unfortunately) is considered a normal year of 36 thousand deaths, we can only have about 1.5 million COVID cases per year (29 million / 20), which works out to 4060 COVID cases per day. If we go with a lower number of 10 times more deadly or take into account that, because of vaccines, most will be protected against severe COVID symptoms, I can see how 10,000 cases per day makes sense.
Still, cases might be the wrong metric to monitor. With so many vaccinated, it seems likely that many might continue to contract COVID but have non-life threatening reactions to it. Cases might remain high while deaths might not.
We would not be doing what we are doing if COVID was non-lethal. With this is mind, the number of deaths is the more appropriate metric to monitor. In order to get to the normal of 36 thousand deaths per year, the United States needs to get closer to 100 COVID deaths per day before we can fully return to normal.