This is the second part of a two part article from the Left ** Lockdown Sceptics site, part one was focused on the evidence for, but mostly against, the sacred face rag. This part deconstructs the muzzle as Purity Signal:
…like the Holy Covid Vaccine, the lesser deity of The Mask, even if it worked, is an unnecessary intervention for most people
The Hidden Curriculum part was clarified in the earlier article but crude précis: the real point of schooling isn’t the reading, riting, and rithmetic, but the sitting up straight, doing what you’re told, and accepting your place in the Order of Things. See also Paolo Freire, Ivan Illich and others of the Deschooling, er, School 
** and no, as per recent very cogent discussions, I have no idea what that word (Left) means or ever was supposed to mean but it sure has passed its best-before-date and is giving off quite a stink.