[skocznymroczny]

> I can tell you the whole 'but they told you masks were useless' thing is a post-facto rationalization to gain some common ground with the less conspiratorial people.

So is the post-facto realization of "we knew masks work, we just didn't want the people to grab all the supply".

[dguaraglia]

That's an oversimplification. The first thing to consider is that there's two types of masks:

* N95 masks

* Everything else

We knew N95 masks worked because that's what professionals use in hospitals. Unfortunately, there was a shortage of PPE so telling people to buy them would put them in direct competition with professionals treating very sick patients. In April 2020 we were looking at a really bleak scenario so there was a very strong incentive to keep professionals alive even if it came at the expense of some citizens (think: doomsday scenario).

We also had no idea whether 'everything else' helped at all. Recommending non-N95 use might have given people a false sense of security that might have played against more effective measures such as extreme social distancing and self-quarantining of people with symptoms.

As knowledge improved, guidance changed. Nothing crazy to see here.

[dguaraglia]

As I explained in another post, originally the consensus was that only N95 masks were somewhat effective. There were no studies on the effectiveness of other masks.

Recommending people use masks could've given people a false sense of security in people and probably acted against more effective measures such as social distancing and self-quarantining of people with symptoms matching those of Covid-19 ('well, I know I have a cough, but I'll just wear a mask and it'll be fine').

Recommending people use the only masks we knew to somewhat work - N95s - would've created a huge problem for hospitals that already were having issues procuring PPE to protect the professionals who were dealing with Covid-19 patients.

Basically, there was no reason for the CDC to recommend masks. Again, there's no need for some nefarious explanation.