The more conspiracy minded started parsing "please don't go out and panic-buy them like you've been doing with toilet paper" as "you don't need masks" almost immediately. It was dumb when it happened, it's still dumb today. I'm sure at least one talking head said something to that effect but that was not actually the consensus message.

"Don't buy these masks unless you're a medical professional" ≠ "Masks don't work unless you're a medical professional."