In fact, at least one study has found plain old surgical masks noninferior to N95 masks for preventing infection by flu (others have found them a little worse, and that's probably the smart way to bet). Common sense suggests that anything that prevents you from touching your mouth would help at least a little.
There is a difference between the best tool for the job and better than nothing. Our civilization has a dangerous habit of mandating the best tool for the job, and then unnecessarily suffering with nothing in an emergency.
Moreover, even if the party line that coarse unsealed masks are completely worthless at protecting the wearer from infection were true, it would still make a big difference in the rate of spread of the virus for everyone to start wearing masks! Who cares what the private benefit is when there is definitely a public benefit? And yes, we could make plenty of masks for everyone if we weren't crippled by regulation, hatred of supply and demand, and the attitude that inaction is better than imperfection.
There is a difference between the best tool for the job and better than nothing. Our civilization has a dangerous habit of mandating the best tool for the job, and then unnecessarily suffering with nothing in an emergency.
Moreover, even if the party line that coarse unsealed masks are completely worthless at protecting the wearer from infection were true, it would still make a big difference in the rate of spread of the virus for everyone to start wearing masks! Who cares what the private benefit is when there is definitely a public benefit? And yes, we could make plenty of masks for everyone if we weren't crippled by regulation, hatred of supply and demand, and the attitude that inaction is better than imperfection.