This article seems to say some of the correct things about respirators and also muddles up some stuff and past tenses the pandemic. But it gives us this gif so I can remind you that mouths are gross in the best of times. https://metro.co.uk/2025/12/10/effective-face-masks-stopping-spread-flu-25348891/

“Carry a mask with you and put it on when you feel like it” is risk assessment by vibes. Vibes cannot tell you if a building is properly ventilated or if there’s adequate air cleaning or if that small group of people has an asymptomatic carrier amongst them.