I had a fairly similar idea a few months back. But mine was more along the lines of they want us to get conditioned to not seeing a nose and mouth cause aliens supposedly don’t really have noses and very small mouths...? Also the masks prevents us from lip reading and reading facial expressions which of course aliens may lack. Yeah, my idea is pretty crazy too!

Any biological disaster, nuclear, chemical, or pollution. Any natural disaster dust storm, major volcanic erruption.

I would be more concerned with conditioning for biological and also natural. Example potential nuke. Or major volcano. If a major volcanic eruption erupted anywhere globally the fallout could mean immediate masks. The same if a few nukes more than one went off. Different masks.

Screw aliens.

The masks in this pandemic are simple policing. If you aren't wearing it you are infected. Simple psychology. It causes policing on those who aren't. Regardless of the profit immediately made from them and the fact they are a false positive and they also clinically make the wearer sicker.