Hi
The way I hear it, most simple masks aren't all that effective in protecting their wearers from viruses. Viruses are very small. They are most effective in stopping larger liquid droplets from coughs or sneezes that viruses 'like' to ride on. And up until recently the medical people didn't know about the large number of unsymptomatic people out there who feel fine but are infectious.
They have always recommended that people who feel ill wear a mask. But now they think that with possible carriers out there ("superspreaders") who don't know they have it, maybe everyone should wear a mask to stop the tiny aerosol droplets.
Aren't all that effective =/= completely ineffective though, and every little helps. They certainly aren't ideal, but anything that offers even rudimentary protection is of great value as it might save your life. Even reducing the viral load on people who do get infected could be very important regarding how bad the infection is.
It's worse in terms of carriers though. We already knew people who are asymptomatic may spread viruses. The idea that it is considered important for symptomatic carriers to weak masks, but asymptomatic carriers were specifically being told
not to wear masks is what I find scandalous.
Even a scarf for these people serves as a very useful barrier, and we could have had all these people wearing masks months ago with no real downside.
When faced with a novel, complex and highly dangerous situation you can't rely on a strict 'evidence based' approach as the perfect information doesn't exist, and by the time it does it's too late. You need to use a precautionary approach based on what you do know, and that certainly would have had people wearing masks.
The whole sorry situation has been naive scientism at its worst.
The problem here in the United States at least is that we have very few manufacturers of masks. Most of the factories that would have made them closed long ago and "off-shored" their production to Asia, mostly. (The US and UK used to have textile industries, believe it or not.) We Import the vast majority of our masks, mostly from China I think. And China has been having some problems of their own recently and they suddenly need all their locally produced masks.
Hopefully this will make people realise that you can't rely on global supply chains of essential products, as when you most need them, they won't be there. An optimised, global system breaks down as it has no redundancy, and redundancy is necessary to cope with shocks.
Countries need to identify what products are essential, foods, equipment, etc. and ensure these are made in their own country. This may entail some protectionist policies for core industries (not for non-core) and would also help local manufacturing economies.
Unfortunately, I have little faith that we will learn from this as we are too short sighted and have short memories. We'll continue going on assuming that the worst can never happen.