RE: Science or propaganda?

After reading the whole study you mentioned, my conclusion would be different from your "Masks do nothing". To me, it seems to only indicate that masks mandates were not efficient in US. In my area, I could think of at least 2 things that could affect mandates efficiency:

• Obviously, people not wearing mask anyways or not correctly (chin diapers, etc...). The latter would skew the mask use metrics as they most likely would describe themselves as wearing masks.
• On the other hand, people wearing masks thinking that makes them invincible and therefore neglecting all other precautions. It was clearly stated masks alone would not suffice.

So, to get a more complete picture, it would be very interesting to see the same kind of data for other countries, especially in Asia, like Singapore.

As a side note, years before COVID was even discovered, my company ran quite a few simulations (Computational Fluid Dynamics) and some experimental tests about the ability of surgical masks to reduce particles spraying. Results clearly indicated it reduced the spraying from the wearer to its surroundings. But I do know this is only one of the ways of spreading.