> What you’re arguing here is not that Fauci was doing science
Well, sure. He was doing his job as a government employee, and right then the job wasn’t to do science and spend the next five years doing a comprehensive study on the virus. It was to make policy recommendations based on science in the sense of “drawing on his many years in the field, and decades of science around the transmissions mechanisms of other, similar diseases” and then to make a guess, yes. All scientists do this, often. Your chemistry teacher in high school made you wear googles when you were mixing liquids even though she didn’t have a paper in Nature definitively showing that the stuff you were mixing that day was even that bad to splash into your eye.
> What you seem to be arguing here is that science wasn’t of any use for making decisions, because the process is too slow.
No, you are arguing that, by insisting that rigorous multi-year studies unequivocally demonstrating the efficacy of masks, specifically with regard to this novel coronavirus that nobody had seen before, would be the only “science” based way to come up with a recommendation, and anything else is “pulling ideas out of thin air”.
I am arguing that all the science around viral transmission generally, influenza, bird flus, mask densities, aerosol spread of saliva and particles, etc. — although yes, not as good as a solid peer reviewed study delivered by scientists from the future who showed up in a time machine — generally is, and I think was in this case also was, of considerable use.
It’s an emergency. Millions of people are dying. It’s spread across the whole world. All any human being can do in that situation is form a hypothesis based on similar, but not perfectly similar, previous experiences. And I think it is obvious to anybody not being intentionally obtuse that the people we want making those guesses, based on the science around other seemingly-similar diseases, are the experts who know the science around those previous diseases, and the efficacies of various methods of prevention, etc., rather than some random guy like me who’s good at writing software and making omelettes, but not familiar with any of the scientific literature around viruses.
And then yeah, obviously modify those guidelines and recommendations (or sure, even laws) as the scientific process continues and better data becomes available.