There was an extremely brief period where public health advice discouraged the general population from masking. This was because there was a huge undersupply for medical workers and because we hadn't fully figured out whether covid aerosolized mere weeks into the pandemic.

Once we had a bit more information in a rapidly evolving situation public health advice switched to recommending masks and stayed that way for years.

We cannot possibly expect public health advice to get everything right immediately during a once-in-a-century pandemic and this error should definitely not be used as a general "wow public health officials are dumb idiots or engaged in a malicious conspiracy", as this error is often used.