Here is an aggregation of studies that come to various conclusions regarding masks.

https://aapsonline.org/mask-facts/

Here is an article from July about mask usage in Europe.

https://www.economist.com/graphic-detail/2020/07/08/face-off...

re: The Economist. "Mask wearing" attitudes in general don't mean much in the context of people who are looking for 100% wearing once you step out of your own door. There are a lot of places that are very compliant indoors, and relatively so outdoors in crowded areas, but not where they're mostly distanced outdoors. To many people, that looks fine. To others, it's horrible.

It's definitely not the first study, I've seen at least 2 or 3 other since March (no links though, sorry). Also the only study that suggested the opposite was a simulation that I think wasn't even peer-reviewed.