[quicklime]

Don’t forget that it was initially thought that the virus could not be transmitted in asymptomatic cases. As time went on, it became clearer that this was happening, and we couldn’t rely on isolation alone.

Anyone could be infected but asymptomatic, you never really know if you’re contagious, and wearing a mask helps with that.

Once this became known, the right thing to do was to change the advice on face coverings.

[basch]

That was another case of information being conveyed that the speakers knew to be untrue, and there was immediate skepticism that the speakers were lying.

[stouset]

Pointing to the fact that some people were skeptical doesn't mean anything. There's immediate (and ongoing) skepticism that this entire damn pandemic is a hoax, FFS.

As with any expert group, the medical community defaulted to going with what they know. In the context of virology, in the overwhelming majority of real-world cases, diseases spread symptomatically. SARS-CoV-19 is genuinely a novel threat in the scale of its transmissivity while asymptomatic and while there was certainly evidence of this early on, it takes non-zero time for this component to be studied, verified, and understood.

You can't (or at least shouldn't) base public policy on reports that haven't yet been corroborated by data and experimental evidence. And being validated after-the-fact doesn't (or at least shouldn't) reflect poorly on decisions made before we had hard data of this virus spreading in a novel fashion.