craftyone
You are right about viruses being able to get through the fabric of cloth masks, but ….
A photon is similar to an electron, which is a tiny (negligible) part of an atom.
A virus is made of largish proteins made, of amino acid molecules, made of dozens of atoms.
The scientific assessments have shown masks to be of some, but rather limited, use in protecting the wearer but do reduce the range of travel of exhaled breaths, and so the chance of other people breathing any virus particles in the breath, being inhaled by bystanders.
World Economic Forum assessment of masks:
Masks have a compounding effect in that they both protect an individual from transmitting and being exposed to infection. The impact of this could, conceivably, be a dramatic reduction of R0. If we are to assume masks are 80% effective in preventing spread on an individual basis, the overall risk-reduction in a single interaction between two people should be 96%. If we are to be conservative and assume that low compliance and mask-quality reduce individual risk by 50% instead of 80%, the overall risk reduction within a single interaction between two people is 75%.