Appeal to authority doesn’t cut it. What matters is research data - if Fauci referenced some, please cite it. The Qatar paper presents very important data on efficacy against disease, but I’ve read through it and there’s nothing in it about transmission.
It’s much easier to study disease incidence in a vaccinated cohort than it is to study transmission from that cohort to unknown other people. So most of the data we have so far on transmission is indirect. Over the past year, I’ve repeatedly corrected people at the opposite extreme - who misunderstood cautious statements that we don’t yet have definitive data on transmission to mean that we have affirmative evidence of the opposite, people mistakenly thinking that we know vaccines don’t prevent transmission. In fact I got pitted just a few days ago for one such correction! In fact, all the data we do have points in the right direction - I certainly agree that it’s likely, it would be strange and shocking if a vaccine that is so remarkably effective against disease did not have a substantial effect in reducing transmission. But it’s not yet so definitive as Fauci suggests in that quote, and the real answer almost certainly will not be black and white, it will be some quantitative reduction in transmission.
Here’s the CDC’s current correctly cautious statement (updated April 2nd), referencing the existing evidence:
A growing body of evidence suggests that fully vaccinated people are less likely to have asymptomatic infection and potentially less likely to transmit SARS-CoV-2 to others. However, further investigation is ongoing.
And see here for one study currently underway that should give us some good direct data on transmission: