They also said "and don't tell anyone that masks might be beneficial"
I missed the word don't. I did see them use "not effective" which is CDC muckmuck for hasn't been proven by multiple rigorous studies to work.
The CDC and Surgeon General ran a campaign with the slogan "STOP buying masks". It doesn't simpler than that.
Agreed. There's a difference between "stop buying masks because we need to save them for nurses" and "stop buying masks because they don't help at all*".