Like most things, masks aren't a black or white, good or bad, precaution for COVID or other viruses.
Without reading this entire thread, the common arguments by "anti-maskers" are that virus particles are too small to be caught in even medical grade masks. That's only partially true, since most airborne pathogens are suspended in droplets, which medical masks catch. There are papers to support this, e.g. example.
"Maskers" may think that any mask is better than none, or that mask mandates are effective measures, and that's also only partially true. Without being part of a total sanitary protocol, even good quality, medical grade masks can be problematic for some. The lax standard for masks, especially when mandated, can give people a false sense of security when not wearing medical grade masks and following other sanitary procedures.
Those extreme labels are fairly useless for many people, who want practical solutions applied effectively.
Basic summary:
1. Medical grade masks help, especially N95, when used as part of a larger sanitary protocol.
2. Masks have disadvantages for some, especially the young while developing socially.
3. Other caveats as described above
When choosing masks, 3M N95 are a good bet. Copies like KN95 can be spotty in quality. Personally, I'm over all the masking when feeling well, having had COVID (caught from a "vaccinated" friend) and natural immunity now. In the unlikely event that I get sick again, I'll be following strict protocols and masking if I have to be around others, which will certainly be avoided.
Will have to see if I've posted here, since this is a bit "deja vu". Then again, we've been rehashing this same crap for years now.