Yes, masks have been shown to reduce Covid-19 transmission, which in turn reduces deaths. At this point, there’s really a preponderance of evidence that says so. (Reduced transmission also means fewer overall cases and fewer opportunities for the virus to mutate into a variant that could be far deadlier or otherwise have more severe consequences than those of the currently-prevailing variants.)

Masks aren’t perfect, and some are better than others, but I’m not sure how this misconception that they have zero efficacy persists.