Ars covers the efficacy of face masks

[Markintosh]

Here's the critical paragraph:

In a 2015 randomized controlled trial involving 1,607 healthcare workers, researchers compared the rate of influenza-like illness in healthcare workers wearing cloth masks or medical masks to those in a control group (which sometimes used masks). Wearing cloth masks resulted in significantly higher rates of infection, the authors found. They also noted that in their test, the cloth masks were only 3 percent effective at blocking particles.

All of those homemade masks may make us feel better, either in wearing them or making them...but the reality is that physical distancing and hand washing are just so more important.