This article wastes its breath by applying science to what is purely a political issue. One side wants individual freedom, one wants a public sign of collective acceptance of authority.

It's not hard to imagine that filtering the air you breath out could stop the spread of respiratory viruses. Nor is it hard to find reasons why they might not work so well. But why are we fighting this proxy "science" battle? It's just pretending to give false credibility to what is a political decision. If they worked completely, many still wouldn't want them because of the implications of allowing authorities to impose something like this on people, and because of the kind of society it creates. And even if they did almost nothing, many would still want them because they make people feel like their fears are taken seriously, like were all doing our part, etc. Let's have this discussion, and not pretend either side cares about science.