> Dr. Fauci acknowledged that he had slowly but deliberately been moving the goal posts... partly on his gut feeling that the country is finally ready to hear what he really thinks.
From wikipedia (https://en.wikipedia.org/wiki/Lie):
> Lying by omission, also known as a continuing misrepresentation or quote mining, occurs when an important fact is left out in order to foster a misconception. Lying by omission includes the failure to correct pre-existing misconceptions.
Dr. Fauci believed that the real range was somewhere between 70 to 90 percent as you pointed out; however, he gave lower estimates to the public because he didn't believe the public was "ready to hear what he really thinks". So not only was he failing to correct pre-existing misconceptions, but he was actively spreading misconceptions about how much of the population he believed needed to be vaccinated. As such, he was lying by omission.
When Dr. Fauci was claiming lower figures: no vaccine had completed clinical trials; variants had not yet emerged; and governments were more willing to implement lockdowns, mask orders, and social distancing restrictions.
If he's guilty of anything, it is misleading the public into thinking he knows what the number is. Nobody knows what the real number is, there are so many confounding factors that it'll take years of research to come up with a decent estimate as to the real herd immunity level of Covid-19 immunisation.
This is a general problem in public scientific messaging. Science deals with uncertainty and nuance, but the fearful public seek certainty and simplicity. People in these positions don't always get the balance right (especially in a crisis), but I wouldn't impune somebody's reputation on that basis.
> “We need to have some humility here,” he added. “We really don’t know what the real number is. I think the real range is somewhere between 70 to 90 percent. But, I’m not going to say 90 percent.”
He's not lying, like the rest of us, he doesn't know. Especially, with the advent of the new variants.
Also, it's odd you're pointing out him giving information during an on-the-record interview as evidence that he's lying.