Why not make masks mandatory everywhere, Serious question ? What's the downside.
These days the governments focus on high risk occupations. These are security guards, bus drivers, care workers, some hospital workers, some retail, some manufacturing and so on. Research also focuses on people with a large number of interactions and very poorly ventilated workplaces (where it's quite hard to work out, but definitely of importance).
The risk outdoors people have had a go at estimating and one study put it at 19x less likely to get the virus outside than inside. Others think it's less than that but at 2 metres distance outside is a vanishingly small chance unless an interaction is very lengthy.