Thanks for the link. The vast majority of the studies cited there are in fact in a hospital setting. I'm skeptical masks worn in the street are going to help more than distancing measures, though they'd probably help in crowded environments like public transport (along with hand washing).
You definitely want to do both & ideally much more. But yet again, even even if mask provided zero protection, as long as it reduces spread from asymptomatic carriers, it is a big win. But for that everyone needs to wear them - which is happening here in Czech republic.
Just today a went for a walk through the second largest Czech city. The weather was nice and there were people in the streets, though a lot less than normally, with the usually crowded spots totally empty due to all the restaurants still being closed.
To cut things short, the number of people without mask I saw during this hour and a half walk that were not wearing a mask ?
Turns out stopping droplets helps slow the spread of a virus that spreads via droplets. Shocker, I know.