And that is the only reason for the claim that masks are useless. Of course they are not useless, Chinese aren't idiots.
A) nobody is making that claim - you are.
So don't turn this into some weird non-fact-based appeal to emotions. The claim that they are useless is because the evidence does not support them. They ARE useful in clinical settings, and heavily required there.
B) there is no evidence for their success:
1) https://www.bbc.co.uk/news/health-51205344 "implementing simple hygiene measures" was vastly more effective." "Although there is a perception that the wearing of facemasks may be beneficial, there is in fact very little evidence of widespread benefit from their use outside of these clinical setting." "routine surgical masks for the public are not an effective protection against viruses or bacteria carried in the air"
2)research study, particularly on leakage: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3306645/
3) efficiacy in Beijin: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5969371/ (again largely leakage)
4) efficacy in 22micron particulate: https://www.ncbi.nlm.nih.gov/pubmed/3470452 (again leakage. but depends on particulate size)
"Im Folgenden ist eine Reihe nachweislich falscher Angaben aufgelistet – etwa der Nutzen von Atemmasken gegen eine Ansteckung"
Source: https://www.faz.net/aktuell/gesellschaft/gesundheit/coronavi...
What they claim is that the uselessness of face masks is proven. Not that the usefulness is unproven. That makes a big difference.
"In what follows, a series of provably false claims are listed - such as the use of breathing masks against contagion".
(Native German speakers can correct me if my translation is inexact)
Since we don't know who is contagious, and we don't have enough masks for everyone, they're essentially "useless". They're quite useful for medical professionals because they're more likely to use sufficient caution than the average person, so it makes sense to reduce panic buying for something that likely won't help the average person so more are available for those that really need it.
And a virus will still penetrate most masks through the sides where air is mainly being pulled in from. So there is more nuance than just "masks are useless"
I guess you can wear them. But given the choice I'd rather have immunity. And I think we should focus more on that.
Droplets (e.g. projectile saliva or mucus) fall out of the air quickly, but this is different.
Here's a source: https://www.nejm.org/doi/full/10.1056/NEJMc2004973, and an upvote.
This is the point I wanted to make but I went with "everyone" instead of "enough"
For what it's worth, I think you'll find here in the US at least a very pigheaded attitude towards wearing masks. And that includes myself. I just don't want to live in a world where everyone has to wear masks. It's soul crushing.