And it was done! Numbers and statistics abound! Maybe you weren’t exposed to the right news sources? Did you forget to subscribe to the COVID mailing list for MBAs?
These are the results of a quick Google search from 2020, which means they are way outdated but also exactly what you are saying should have happened. And we didn’t even have large scale studies testing how effective masks were against the virus until what, October, November?
The CDC says a data analysis shows that just a 15 percent increase in mask wearing could prevent the need for lockdowns and help reduce economic losses up to $1 trillion.
ETA: As for the high profile public messaging, there were political considerations for the CDC director. Specifically regarding messaging of masks saving lives. Remember this?
ETA2: You may be interested in the discussion we had here, at the time, and the many cites given.
~Max