On masks, I don’t think anyone is advocating that they are the silver bullet, but they have a part to play. If you’re in a cabin or 180 people and all are wearing it properly, the amount of virus is going to be reduced substantially. But everyone has a part to play - if someone isn’t wearing one, or wearing it wrongly, it can affect everyone in the vicinity.
Masks will not eliminate infection, but may well be reducing the severity. Masks will reduce the momentum of the germ.