Sorry, is there a scientific point there?
The point I was making is that scientific evidence occurs on different dimensions, which can be pieced together to form a policy decision. I don't know the details of this "study" which you refer to, but any sensible interpretation would need more than one small graphic. It would also need to be interpreted in the context of other studies which aggregate, sometime in meta analyses, to inform a more reliable opinion.
The other, pragmatic, approach is to estimate what the benefit risk is. The only risk of masks is bruising of your libertarian expectation to do whatever the F you want whether it hurts anybody else or not. Any reasonable person would conclude that there may, at least, be a benefit to wearing a mask as part of a package of measures, so what's the harm.