I used to do contamination compliance measurements for biotech and nanotech with particle counters capable of detecting particles down to 80nm  (the size of a coronavirus).  In a controlled environment with laminar flow in a class one cleanroom there is no difference between wearing a mask or not with regards to particles in the sub-micron range when the sensor is placed about a foot in front of your face.  In fact, if you cough you get so many sub-half micron particles that the sensor of our machine needed to be sent back to the factory to be cleaned as it would ruin it.  There isn't a mask manufacturer out there that will claim their masks are capable of impeding viral transmission, in fact they state precisely the opposite on their packaging. There's no way any study, now that this issue has been so politicized and corrupted by bribed-science, is ever going to convince me that a simple mask in open air does jack against a viral particle anymore than a chain-link fence stops mosquitoes.   Every bit of my career experience says otherwise, as does the pre-Covid published literature.