The answer is that it doesn't matter. Masks, social distancing and lockdowns are NPIs not drugs. It's enough signal that everyone gets masked and the burden of proof is on those who want to demask to provide level 1 evidence it won't cause excess mortality/morbidity.
https://twitter.com/GidMK/status/1461566094330580992
The burden of proof to come up with evidence to substantiate their position falls on those who propose the potentially unsafe course of action. With novel drugs, that falls on the prescriber/manufacturer of the drug. With NPIs it is the de-prescriber of precautionary measures
There is no level 1a+++ evidence for the efficacy of lockdowns, handwashing, or social distancing for COVID. That is not grounds for de-prescription of these precautionary NPIs. The burden of proof falls on those who wish to de-prescribe them to prove it won't increase mortality
Masking for COVID to filter the air is like boiling drinking water in cholera. There is no level 1a evidence proving that boiling contaminated drinking water reduces mortality in cholera. Yet it would be madness to not recommend it while people die, because of a lack of an RCT 
An RCT of boiling drinking water for cholera would involve getting those in the control group to drink unsterilised drinking water to see if they died more. The big question is, whether here or with masking in COVID, is whether that is even ethical to do now. I doubt it is
The burden of proof here falls on those who propose encouraging people to drink unboiled water during a cholera pandemic. Show us your level 1a+++ evidence that this won't result in senseless mass deaths. Until then the water gets boiled
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