The CDC said that masks would not be very effective at preventing you from getting the disease if you don't already have it. They are however extremely effective at preventing you from spreading it if you are already infected.
THAT is the difference.
Yes, masks (not just N95 masks either) were indeed in short supply when the pandemic hit and the morons were buying them up like hot cakes in an effort to be "protected" from getting the virus. Except even if you are wearing a mask the virus can get in your eyes or get on your skin and get wiped on you nose, mouth, and eyes and you can get it. The only way to prevent the spread is for those who are infected to stop spreading the disease and masks are extremely effective at that.
Fauci and the CDC didn't lie, they were trying to stop idiots from hoarding masks that were in desperate need in hospitals and immediate care facilities. They just underestimate how unfathomably dumb you all are.