The answer to the question is that cloth masks are effective against viruses with a droplet based spread, but not against a fully airborne virus.
Note that cloth masks almost completely did away with last year's Flu season, while we were right in the middle of a huge Covid surge.
NEW YORK (AP) — February is usually the peak of flu season, with doctors’ offices and hospitals packed with suffering patients. But not this year.
Nationally, “this is the lowest flu season we’ve had on record,” according to a surveillance system that is about 25 years old, said Lynnette Brammer of the U.S. Centers for Disease Control and Prevention.
https://apnews.com/article/flu-has-disappeared-us-pandemic-2...
https://www.king5.com/article/news/health/coronavirus/zero-f...
I'm just asking if we have info on population spread effects for masks / no masks.
"Masks won't protect you" isn't an answer to that question. I don't wear a mask when requested by local guidelines or businesses as some kind of guarantee that I don't get COVID.
And yes, having kids not all go to school and then return to their families on a daily basis would probably have a much bigger affect on community spread. But if we can't get political will for masks or vaccinations then I don't know where we're going to find it for another round of kids staying home.